21039332525 has 18 divisors (see below), whose sum is σ = 26993396010. Its totient is φ = 16248053920.

The previous prime is 21039332519. The next prime is 21039332527. The reversal of 21039332525 is 52523393012.

It can be written as a sum of positive squares in 3 ways, for example, as 1421968681 + 19617363844 = 37709^2 + 140062^2 .

It is not a de Polignac number, because 21039332525 - 2³⁴ = 3859463341 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21039332527) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 3902882 + ... + 3908268.

Almost surely, 2^21039332525 is an apocalyptic number.

21039332525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21039332525 is a deficient number, since it is larger than the sum of its proper divisors (5954063485).

21039332525 is an frugal number, since it uses more digits than its factorization.

21039332525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10813 (or 5421 counting only the distinct ones).

The product of its (nonzero) digits is 48600, while the sum is 35.

The spelling of 21039332525 in words is "twenty-one billion, thirty-nine million, three hundred thirty-two thousand, five hundred twenty-five".