20505625860 has 48 divisors (see below), whose sum is σ = 58751009856. Its totient is φ = 5340999552.

The previous prime is 20505625843. The next prime is 20505625883. The reversal of 20505625860 is 6852650502.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3971379 + ... + 3976538.

It is an arithmetic number, because the mean of its divisors is an integer number (1223979372).

Almost surely, 2^20505625860 is an apocalyptic number.

20505625860 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20505625860 is an abundant number, since it is smaller than the sum of its proper divisors (38245383996).

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

20505625860 is a wasteful number, since it uses less digits than its factorization.

20505625860 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7947972 (or 7947970 counting only the distinct ones).

The product of its (nonzero) digits is 144000, while the sum is 39.

The spelling of 20505625860 in words is "twenty billion, five hundred five million, six hundred twenty-five thousand, eight hundred sixty".