21402532215 has 24 divisors (see below), whose sum is σ = 38294425728. Its totient is φ = 11046467520.

The previous prime is 21402532213. The next prime is 21402532219. The reversal of 21402532215 is 51223520412.

It is not a de Polignac number, because 21402532215 - 2¹ = 21402532213 is a prime.

It is a super-2 number, since 2×21402532215² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21402532213) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7669764 + ... + 7672553.

It is an arithmetic number, because the mean of its divisors is an integer number (1595601072).

Almost surely, 2^21402532215 is an apocalyptic number.

21402532215 is a deficient number, since it is larger than the sum of its proper divisors (16891893513).

21402532215 is a wasteful number, since it uses less digits than its factorization.

21402532215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15342359 (or 15342356 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 27.

The spelling of 21402532215 in words is "twenty-one billion, four hundred two million, five hundred thirty-two thousand, two hundred fifteen".