21200400400212 has 72 divisors (see below), whose sum is σ = 58480173303552. Its totient is φ = 6422334844800.

The previous prime is 21200400400189. The next prime is 21200400400253.

21200400400212 is a `hidden beast` number, since 2 + 1 + 200 + 40 + 0 + 400 + 21 + 2 = 666.

21200400400212 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7198089 + ... + 9706352.

It is an arithmetic number, because the mean of its divisors is an integer number (812224629216).

Almost surely, 2^{21200400400212} is an apocalyptic number.

21200400400212 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21200400400212 is an abundant number, since it is smaller than the sum of its proper divisors (37279772903340).

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

21200400400212 is a wasteful number, since it uses less digits than its factorization.

21200400400212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16907629 (or 16907624 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

It can be divided in two parts, 21200400 and 400212, that added together give a palindrome (21600612).

The spelling of 21200400400212 in words is "twenty-one trillion, two hundred billion, four hundred million, four hundred thousand, two hundred twelve".