21271667524 has 6 divisors (see below), whose sum is σ = 37225418174. Its totient is φ = 10635833760.

The previous prime is 21271667509. The next prime is 21271667579. The reversal of 21271667524 is 42576617212.

It can be written as a sum of positive squares in only one way, i.e., 16995815424 + 4275852100 = 130368^2 + 65390^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2658958437 + ... + 2658958444.

Almost surely, 2^21271667524 is an apocalyptic number.

It is an amenable number.

21271667524 is a deficient number, since it is larger than the sum of its proper divisors (15953750650).

21271667524 is a wasteful number, since it uses less digits than its factorization.

21271667524 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5317916885 (or 5317916883 counting only the distinct ones).

The product of its digits is 282240, while the sum is 43.

The spelling of 21271667524 in words is "twenty-one billion, two hundred seventy-one million, six hundred sixty-seven thousand, five hundred twenty-four".