21545020222400 has 84 divisors (see below), whose sum is σ = 53067714966720. Its totient is φ = 8609311180800.

The previous prime is 21545020222391. The next prime is 21545020222409. The reversal of 21545020222400 is 422202054512.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21545020222391) and next prime (21545020222409).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21545020222409) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5208365 + ... + 8379564.

Almost surely, 2^{21545020222400} is an apocalyptic number.

21545020222400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21545020222400 is an abundant number, since it is smaller than the sum of its proper divisors (31522694744320).

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

21545020222400 is a wasteful number, since it uses less digits than its factorization.

21545020222400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13588942 (or 13588927 counting only the distinct ones).

The product of its (nonzero) digits is 12800, while the sum is 29.

Adding to 21545020222400 its reverse (422202054512), we get a palindrome (21967222276912).

The spelling of 21545020222400 in words is "twenty-one trillion, five hundred forty-five billion, twenty million, two hundred twenty-two thousand, four hundred".