21495265 has 16 divisors (see below), whose sum is σ = 28259136. Its totient is φ = 15566400.

The previous prime is 21495239. The next prime is 21495269. The reversal of 21495265 is 56259412.

It is a happy number.

It is not a de Polignac number, because 21495265 - 2⁵ = 21495233 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21495265.

It is not an unprimeable number, because it can be changed into a prime (21495269) 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, 14875 + ... + 16255.

It is an arithmetic number, because the mean of its divisors is an integer number (1766196).

Almost surely, 2^21495265 is an apocalyptic number.

It is an amenable number.

21495265 is a deficient number, since it is larger than the sum of its proper divisors (6763871).

21495265 is a wasteful number, since it uses less digits than its factorization.

21495265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1680.

The product of its digits is 21600, while the sum is 34.

The square root of 21495265 is about 4636.2986314516. The cubic root of 21495265 is about 278.0444738468.

The spelling of 21495265 in words is "twenty-one million, four hundred ninety-five thousand, two hundred sixty-five".