20661159057 has 32 divisors (see below), whose sum is σ = 34353936384. Its totient is φ = 10730534400.

The previous prime is 20661158971. The next prime is 20661159067. The reversal of 20661159057 is 75095116602.

It is not a de Polignac number, because 20661159057 - 2⁸ = 20661158801 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20661159067) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 1345332 + ... + 1360602.

It is an arithmetic number, because the mean of its divisors is an integer number (1073560512).

Almost surely, 2^20661159057 is an apocalyptic number.

It is an amenable number.

20661159057 is a deficient number, since it is larger than the sum of its proper divisors (13692777327).

20661159057 is a wasteful number, since it uses less digits than its factorization.

20661159057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21149.

The product of its (nonzero) digits is 113400, while the sum is 42.

The spelling of 20661159057 in words is "twenty billion, six hundred sixty-one million, one hundred fifty-nine thousand, fifty-seven".