20521124664 has 32 divisors (see below), whose sum is σ = 51484110720. Its totient is φ = 6816201696.

The previous prime is 20521124641. The next prime is 20521124669. The reversal of 20521124664 is 46642112502.

It is a super-2 number, since 2×20521124664² (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 (20521124669) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1503892 + ... + 1517475.

It is an arithmetic number, because the mean of its divisors is an integer number (1608878460).

Almost surely, 2^20521124664 is an apocalyptic number.

20521124664 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

20521124664 is an abundant number, since it is smaller than the sum of its proper divisors (30962986056).

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

20521124664 is a wasteful number, since it uses less digits than its factorization.

20521124664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3021659 (or 3021655 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 33.

The spelling of 20521124664 in words is "twenty billion, five hundred twenty-one million, one hundred twenty-four thousand, six hundred sixty-four".