21136746852 has 90 divisors (see below), whose sum is σ = 59833176018. Its totient is φ = 6503597568.

The previous prime is 21136746847. The next prime is 21136746857. The reversal of 21136746852 is 25864763112.

21136746852 is a `hidden beast` number, since 2 + 1 + 136 + 7 + 468 + 52 = 666.

It is an interprime number because it is at equal distance from previous prime (21136746847) and next prime (21136746857).

It can be written as a sum of positive squares in 3 ways, for example, as 1439747136 + 19696999716 = 37944^2 + 140346^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21136746798 and 21136746807.

It is not an unprimeable number, because it can be changed into a prime (21136746857) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 138253 + ... + 247764.

Almost surely, 2^21136746852 is an apocalyptic number.

It is an amenable number.

21136746852 is an abundant number, since it is smaller than the sum of its proper divisors (38696429166).

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

21136746852 is a wasteful number, since it uses less digits than its factorization.

21136746852 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 386059 (or 386035 counting only the distinct ones).

The product of its digits is 483840, while the sum is 45.

The spelling of 21136746852 in words is "twenty-one billion, one hundred thirty-six million, seven hundred forty-six thousand, eight hundred fifty-two".