21903316 has 12 divisors (see below), whose sum is σ = 39146688. Its totient is φ = 10718552.

The previous prime is 21903313. The next prime is 21903319. The reversal of 21903316 is 61330912.

It is an interprime number because it is at equal distance from previous prime (21903313) and next prime (21903319).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21903311) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 58066 + ... + 58441.

It is an arithmetic number, because the mean of its divisors is an integer number (3262224).

Almost surely, 2^21903316 is an apocalyptic number.

It is an amenable number.

21903316 is a deficient number, since it is larger than the sum of its proper divisors (17243372).

21903316 is a wasteful number, since it uses less digits than its factorization.

21903316 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116558 (or 116556 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 25.

The square root of 21903316 is about 4680.0978622247. The cubic root of 21903316 is about 279.7928569982.

The spelling of 21903316 in words is "twenty-one million, nine hundred three thousand, three hundred sixteen".