Synonyms for Number one:

n.

bob, Bobbed, braid, chignon, Herself, Yourself, me, Myself, afro, buzz cut, Himself, close, bangs, bun, beehive. concept album, liner notes, 45, album, cassette, leader, flip side, precede, discography, bootleg, long-playing record, disk, front-runner. magnate, mogul, authority figure, vip, mover and shaker, eminence, leading light, figure, prime mover, a force to be reckoned with. bunny, bang, birdie, bow-wow, cross, choo-choo, cold, boo-boo. basic, elementary. self-deception, self-image, self-styled, image, self-critical, self-described, self-proclaimed, do someone/yourself an injustice, ego. most important person or thing (noun)
leader.
number one (noun)
first, number 1.

Other synonyms:

self-deception, self-described, self-proclaimed, front-runner, self-critical, self-styled, self-image. ego. image. leader. Other relevant words:
front-runner, Himself, Yourself, ego, Herself, leader, Myself.