21300550864 has 80 divisors (see below), whose sum is σ = 44192203264. Its totient is φ = 9928396800.

The previous prime is 21300550829. The next prime is 21300550867. The reversal of 21300550864 is 46805500312.

It is a super-2 number, since 2×21300550864² (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 (21300550867) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1550104 + ... + 1563784.

Almost surely, 2^21300550864 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21300550864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22096101632).

21300550864 is an abundant number, since it is smaller than the sum of its proper divisors (22891652400).

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

21300550864 is a wasteful number, since it uses less digits than its factorization.

21300550864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13836 (or 13830 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 34.

The spelling of 21300550864 in words is "twenty-one billion, three hundred million, five hundred fifty thousand, eight hundred sixty-four".