20879142977 has 16 divisors (see below), whose sum is σ = 27562384512. Its totient is φ = 15312433920.

The previous prime is 20879142953. The next prime is 20879143007. The reversal of 20879142977 is 77924197802.

It is not a de Polignac number, because 20879142977 - 2⁶ = 20879142913 is a prime.

It is a super-2 number, since 2×20879142977² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20879142917) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 7973918 + ... + 7976535.

It is an arithmetic number, because the mean of its divisors is an integer number (1722649032).

Almost surely, 2^20879142977 is an apocalyptic number.

It is an amenable number.

20879142977 is a deficient number, since it is larger than the sum of its proper divisors (6683241535).

20879142977 is a wasteful number, since it uses less digits than its factorization.

20879142977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15950488.

The product of its (nonzero) digits is 3556224, while the sum is 56.

The spelling of 20879142977 in words is "twenty billion, eight hundred seventy-nine million, one hundred forty-two thousand, nine hundred seventy-seven".