20556271660 has 24 divisors (see below), whose sum is σ = 43875848016. Its totient is φ = 8087712960.

The previous prime is 20556271657. The next prime is 20556271691. The reversal of 20556271660 is 6617265502.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8423482 + ... + 8425921.

It is an arithmetic number, because the mean of its divisors is an integer number (1828160334).

Almost surely, 2^20556271660 is an apocalyptic number.

20556271660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20556271660 is an abundant number, since it is smaller than the sum of its proper divisors (23319576356).

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

20556271660 is a wasteful number, since it uses less digits than its factorization.

20556271660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16849473 (or 16849471 counting only the distinct ones).

The product of its (nonzero) digits is 151200, while the sum is 40.

The spelling of 20556271660 in words is "twenty billion, five hundred fifty-six million, two hundred seventy-one thousand, six hundred sixty".