21724507464 has 64 divisors (see below), whose sum is σ = 59738402880. Its totient is φ = 6583174400.

The previous prime is 21724507447. The next prime is 21724507477. The reversal of 21724507464 is 46470542712.

It is a super-2 number, since 2×21724507464² (a number of 21 digits) contains 22 as substring.

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, 308097 + ... + 371984.

It is an arithmetic number, because the mean of its divisors is an integer number (933412545).

Almost surely, 2^21724507464 is an apocalyptic number.

21724507464 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21724507464 is an abundant number, since it is smaller than the sum of its proper divisors (38013895416).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21724507464 is a wasteful number, since it uses less digits than its factorization.

21724507464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 680123 (or 680097 counting only the distinct ones).

The product of its (nonzero) digits is 376320, while the sum is 42.

The spelling of 21724507464 in words is "twenty-one billion, seven hundred twenty-four million, five hundred seven thousand, four hundred sixty-four".