21253650215 has 16 divisors (see below), whose sum is σ = 29420278272. Its totient is φ = 14437724064.

The previous prime is 21253650179. The next prime is 21253650247. The reversal of 21253650215 is 51205635212.

It is a cyclic number.

It is not a de Polignac number, because 21253650215 - 2⁸ = 21253649959 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, 2833859 + ... + 2841348.

It is an arithmetic number, because the mean of its divisors is an integer number (1838767392).

Almost surely, 2^21253650215 is an apocalyptic number.

21253650215 is a deficient number, since it is larger than the sum of its proper divisors (8166628057).

21253650215 is a wasteful number, since it uses less digits than its factorization.

21253650215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5675326.

The product of its (nonzero) digits is 18000, while the sum is 32.

The spelling of 21253650215 in words is "twenty-one billion, two hundred fifty-three million, six hundred fifty thousand, two hundred fifteen".