21620614601525 has 12 divisors (see below), whose sum is σ = 26809734893412. Its totient is φ = 17296380205440.

The previous prime is 21620614601513. The next prime is 21620614601533. The reversal of 21620614601525 is 52510641602612.

It can be written as a sum of positive squares in 6 ways, for example, as 6855301137169 + 14765313464356 = 2618263^2 + 3842566^2 .

It is not a de Polignac number, because 21620614601525 - 2⁸ = 21620614601269 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1286399 + ... + 6700451.

It is an arithmetic number, because the mean of its divisors is an integer number (2234144574451).

Almost surely, 2^{21620614601525} is an apocalyptic number.

21620614601525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21620614601525 is a deficient number, since it is larger than the sum of its proper divisors (5189120291887).

21620614601525 is a wasteful number, since it uses less digits than its factorization.

21620614601525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5573800 (or 5573795 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 41.

The spelling of 21620614601525 in words is "twenty-one trillion, six hundred twenty billion, six hundred fourteen million, six hundred one thousand, five hundred twenty-five".