21325907815 has 16 divisors (see below), whose sum is σ = 25767492480. Its totient is φ = 16943500800.

The previous prime is 21325907803. The next prime is 21325907851. The reversal of 21325907815 is 51870952312.

It is a happy number.

It is not a de Polignac number, because 21325907815 - 2¹⁵ = 21325875047 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 435922 + ... + 482368.

It is an arithmetic number, because the mean of its divisors is an integer number (1610468280).

Almost surely, 2^21325907815 is an apocalyptic number.

21325907815 is a deficient number, since it is larger than the sum of its proper divisors (4441584665).

21325907815 is a wasteful number, since it uses less digits than its factorization.

21325907815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47082.

The product of its (nonzero) digits is 151200, while the sum is 43.

The spelling of 21325907815 in words is "twenty-one billion, three hundred twenty-five million, nine hundred seven thousand, eight hundred fifteen".