21795263 has 16 divisors (see below), whose sum is σ = 26271744. Its totient is φ = 17686080.

The previous prime is 21795259. The next prime is 21795289. The reversal of 21795263 is 36259712.

It is a cyclic number.

It is not a de Polignac number, because 21795263 - 2² = 21795259 is a prime.

It is a Smith number, since the sum of its digits (35) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21795233) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9131 + ... + 11267.

It is an arithmetic number, because the mean of its divisors is an integer number (1641984).

Almost surely, 2^21795263 is an apocalyptic number.

21795263 is a deficient number, since it is larger than the sum of its proper divisors (4476481).

21795263 is a wasteful number, since it uses less digits than its factorization.

21795263 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2222.

The product of its digits is 22680, while the sum is 35.

The square root of 21795263 is about 4668.5397074460. The cubic root of 21795263 is about 279.3320088428.

The spelling of 21795263 in words is "twenty-one million, seven hundred ninety-five thousand, two hundred sixty-three".