20856679930 has 16 divisors (see below), whose sum is σ = 37543785120. Its totient is φ = 8342280592.

The previous prime is 20856679897. The next prime is 20856679973. The reversal of 20856679930 is 3997665802.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 280557 + ... + 347023.

It is an arithmetic number, because the mean of its divisors is an integer number (2346486570).

Almost surely, 2^20856679930 is an apocalyptic number.

20856679930 is a deficient number, since it is larger than the sum of its proper divisors (16687105190).

20856679930 is a wasteful number, since it uses less digits than its factorization.

20856679930 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97853.

The product of its (nonzero) digits is 4898880, while the sum is 55.

The spelling of 20856679930 in words is "twenty billion, eight hundred fifty-six million, six hundred seventy-nine thousand, nine hundred thirty".