21110513525 has 12 divisors (see below), whose sum is σ = 26785806432. Its totient is φ = 16495656240.

The previous prime is 21110513513. The next prime is 21110513527. The reversal of 21110513525 is 52531501112.

It is not a de Polignac number, because 21110513525 - 2⁶ = 21110513461 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21110513494 and 21110513503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21110513527) 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, 9817769 + ... + 9819918.

It is an arithmetic number, because the mean of its divisors is an integer number (2232150536).

Almost surely, 2^21110513525 is an apocalyptic number.

21110513525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21110513525 is a deficient number, since it is larger than the sum of its proper divisors (5675292907).

21110513525 is a wasteful number, since it uses less digits than its factorization.

21110513525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19637740 (or 19637735 counting only the distinct ones).

The product of its (nonzero) digits is 1500, while the sum is 26.

The spelling of 21110513525 in words is "twenty-one billion, one hundred ten million, five hundred thirteen thousand, five hundred twenty-five".