20957049979 has 8 divisors (see below), whose sum is σ = 21021930000. Its totient is φ = 20892237312.

The previous prime is 20957049977. The next prime is 20957050003. The reversal of 20957049979 is 97994075902.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20957049979 - 2¹ = 20957049977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20957049977) 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 7 ways as a sum of consecutive naturals, for example, 646347 + ... + 677995.

It is an arithmetic number, because the mean of its divisors is an integer number (2627741250).

Almost surely, 2^20957049979 is an apocalyptic number.

20957049979 is a deficient number, since it is larger than the sum of its proper divisors (64880021).

20957049979 is a wasteful number, since it uses less digits than its factorization.

20957049979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33677.

The product of its (nonzero) digits is 12859560, while the sum is 61.

The spelling of 20957049979 in words is "twenty billion, nine hundred fifty-seven million, forty-nine thousand, nine hundred seventy-nine".