21053205234 has 20 divisors (see below), whose sum is σ = 47174775054. Its totient is φ = 7017735024.

The previous prime is 21053205223. The next prime is 21053205301. The reversal of 21053205234 is 43250235012.

It is a happy number.

21053205234 is a `hidden beast` number, since 2 + 105 + 32 + 0 + 523 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 16229486025 + 4823719209 = 127395^2 + 69453^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 21053205198 and 21053205207.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 64978867 + ... + 64979190.

Almost surely, 2^21053205234 is an apocalyptic number.

21053205234 is an abundant number, since it is smaller than the sum of its proper divisors (26121569820).

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

21053205234 is a wasteful number, since it uses less digits than its factorization.

21053205234 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129958071 (or 129958062 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 27.

The spelling of 21053205234 in words is "twenty-one billion, fifty-three million, two hundred five thousand, two hundred thirty-four".