21902313 has 8 divisors (see below), whose sum is σ = 29224800. Its totient is φ = 14590688.

The previous prime is 21902299. The next prime is 21902317. The reversal of 21902313 is 31320912.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21902313 - 2⁴ = 21902297 is a prime.

It is a super-3 number, since 3×21902313³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a self number, because there is not a number n which added to its sum of digits gives 21902313.

It is not an unprimeable number, because it can be changed into a prime (21902317) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5893 + ... + 8861.

It is an arithmetic number, because the mean of its divisors is an integer number (3653100).

Almost surely, 2^21902313 is an apocalyptic number.

It is an amenable number.

21902313 is a deficient number, since it is larger than the sum of its proper divisors (7322487).

21902313 is a wasteful number, since it uses less digits than its factorization.

21902313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5431.

The product of its (nonzero) digits is 324, while the sum is 21.

The square root of 21902313 is about 4679.9907051190. The cubic root of 21902313 is about 279.7885861606.

The spelling of 21902313 in words is "twenty-one million, nine hundred two thousand, three hundred thirteen".