21464021631 has 64 divisors (see below), whose sum is σ = 32926279680. Its totient is φ = 12328122240.

The previous prime is 21464021611. The next prime is 21464021651. The reversal of 21464021631 is 13612046412.

It is an interprime number because it is at equal distance from previous prime (21464021611) and next prime (21464021651).

It is not a de Polignac number, because 21464021631 - 2¹⁴ = 21464005247 is a prime.

It is a super-2 number, since 2×21464021631² (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 (21464021611) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 16728916 + ... + 16730198.

It is an arithmetic number, because the mean of its divisors is an integer number (514473120).

Almost surely, 2^21464021631 is an apocalyptic number.

21464021631 is a deficient number, since it is larger than the sum of its proper divisors (11462258049).

21464021631 is a wasteful number, since it uses less digits than its factorization.

21464021631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1636.

The product of its (nonzero) digits is 6912, while the sum is 30.

The spelling of 21464021631 in words is "twenty-one billion, four hundred sixty-four million, twenty-one thousand, six hundred thirty-one".