21520131052 has 36 divisors (see below), whose sum is σ = 44827665960. Its totient is φ = 9008423424.

The previous prime is 21520131049. The next prime is 21520131053. The reversal of 21520131052 is 25013102512.

It is not an unprimeable number, because it can be changed into a prime (21520131053) 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, 1268277 + ... + 1285132.

Almost surely, 2^21520131052 is an apocalyptic number.

It is an amenable number.

21520131052 is an abundant number, since it is smaller than the sum of its proper divisors (23307534908).

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

21520131052 is a wasteful number, since it uses less digits than its factorization.

21520131052 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2553470 (or 2553461 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 22.

Adding to 21520131052 its reverse (25013102512), we get a palindrome (46533233564).

The spelling of 21520131052 in words is "twenty-one billion, five hundred twenty million, one hundred thirty-one thousand, fifty-two".