21150638400 has 504 divisors, whose sum is σ = 75033550720. Its totient is φ = 5214044160.

The previous prime is 21150638381. The next prime is 21150638413. The reversal of 21150638400 is 483605112.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 109588704 + ... + 109588896.

Almost surely, 2^21150638400 is an apocalyptic number.

21150638400 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 21150638400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37516775360).

21150638400 is an abundant number, since it is smaller than the sum of its proper divisors (53882912320).

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

21150638400 is a wasteful number, since it uses less digits than its factorization.

21150638400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 331 (or 299 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 30.

The spelling of 21150638400 in words is "twenty-one billion, one hundred fifty million, six hundred thirty-eight thousand, four hundred".