20831924117 has 4 divisors (see below), whose sum is σ = 22057331436. Its totient is φ = 19606516800.

The previous prime is 20831924111. The next prime is 20831924161. The reversal of 20831924117 is 71142913802.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 8304494641 + 12527429476 = 91129^2 + 111926^2 .

It is a cyclic number.

It is not a de Polignac number, because 20831924117 - 2⁴ = 20831924101 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20831924111) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 612703634 + ... + 612703667.

It is an arithmetic number, because the mean of its divisors is an integer number (5514332859).

Almost surely, 2^20831924117 is an apocalyptic number.

It is an amenable number.

20831924117 is a deficient number, since it is larger than the sum of its proper divisors (1225407319).

20831924117 is a wasteful number, since it uses less digits than its factorization.

20831924117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1225407318.

The product of its (nonzero) digits is 24192, while the sum is 38.

The spelling of 20831924117 in words is "twenty billion, eight hundred thirty-one million, nine hundred twenty-four thousand, one hundred seventeen".