21464631 has 12 divisors (see below), whose sum is σ = 31089240. Its totient is φ = 14270640.

The previous prime is 21464627. The next prime is 21464633. The reversal of 21464631 is 13646412.

21464631 is a `hidden beast` number, since 2 + 14 + 646 + 3 + 1 = 666.

It is not a de Polignac number, because 21464631 - 2² = 21464627 is a prime.

It is a super-2 number, since 2×21464631² = 921460767932322, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21464595 and 21464604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21464633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 436 + ... + 6566.

It is an arithmetic number, because the mean of its divisors is an integer number (2590770).

Almost surely, 2^21464631 is an apocalyptic number.

21464631 is a deficient number, since it is larger than the sum of its proper divisors (9624609).

21464631 is a wasteful number, since it uses less digits than its factorization.

21464631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6526 (or 6523 counting only the distinct ones).

The product of its digits is 3456, while the sum is 27.

The square root of 21464631 is about 4632.9937405526. The cubic root of 21464631 is about 277.9123259231.

The spelling of 21464631 in words is "twenty-one million, four hundred sixty-four thousand, six hundred thirty-one".