21024387864400 has 120 divisors (see below), whose sum is σ = 50710200376160. Its totient is φ = 8376625082880.

The previous prime is 21024387864391. The next prime is 21024387864407. The reversal of 21024387864400 is 446878342012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21024387864407) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 353089831 + ... + 353149369.

Almost surely, 2^{21024387864400} is an apocalyptic number.

21024387864400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21024387864400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25355100188080).

21024387864400 is an abundant number, since it is smaller than the sum of its proper divisors (29685812511760).

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

21024387864400 is a wasteful number, since it uses less digits than its factorization.

21024387864400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63021 (or 63010 counting only the distinct ones).

The product of its (nonzero) digits is 2064384, while the sum is 49.

The spelling of 21024387864400 in words is "twenty-one trillion, twenty-four billion, three hundred eighty-seven million, eight hundred sixty-four thousand, four hundred".