20910804931 has 4 divisors (see below), whose sum is σ = 21631867200. Its totient is φ = 20189742664.

The previous prime is 20910804919. The next prime is 20910804949. The reversal of 20910804931 is 13940801902.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20910804931 - 2⁹ = 20910804419 is a prime.

It is a super-2 number, since 2×20910804931² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20910804631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 360531091 + ... + 360531148.

It is an arithmetic number, because the mean of its divisors is an integer number (5407966800).

Almost surely, 2^20910804931 is an apocalyptic number.

20910804931 is a deficient number, since it is larger than the sum of its proper divisors (721062269).

20910804931 is an equidigital number, since it uses as much as digits as its factorization.

20910804931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 721062268.

The product of its (nonzero) digits is 15552, while the sum is 37.

The spelling of 20910804931 in words is "twenty billion, nine hundred ten million, eight hundred four thousand, nine hundred thirty-one".