20656540025 has 24 divisors (see below), whose sum is σ = 27971629344. Its totient is φ = 15007366400.

The previous prime is 20656540019. The next prime is 20656540043. The reversal of 20656540025 is 52004565602.

It is not a de Polignac number, because 20656540025 - 2¹⁸ = 20656277881 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 230234 + ... + 307116.

It is an arithmetic number, because the mean of its divisors is an integer number (1165484556).

Almost surely, 2^20656540025 is an apocalyptic number.

20656540025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20656540025 is a deficient number, since it is larger than the sum of its proper divisors (7315089319).

20656540025 is a wasteful number, since it uses less digits than its factorization.

20656540025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77881 (or 77876 counting only the distinct ones).

The product of its (nonzero) digits is 72000, while the sum is 35.

The spelling of 20656540025 in words is "twenty billion, six hundred fifty-six million, five hundred forty thousand, twenty-five".