20313123021 has 6 divisors (see below), whose sum is σ = 29341177710. Its totient is φ = 13542082008.

The previous prime is 20313123011. The next prime is 20313123097. The reversal of 20313123021 is 12032131302.

20313123021 is a `hidden beast` number, since 20 + 31 + 312 + 302 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 16438060521 + 3875062500 = 128211^2 + 62250^2 .

It is not a de Polignac number, because 20313123021 - 2²³ = 20304734413 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20313122985 and 20313123003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20313123011) 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 5 ways as a sum of consecutive naturals, for example, 1128506826 + ... + 1128506843.

It is an arithmetic number, because the mean of its divisors is an integer number (4890196285).

Almost surely, 2^20313123021 is an apocalyptic number.

It is an amenable number.

20313123021 is a deficient number, since it is larger than the sum of its proper divisors (9028054689).

20313123021 is a wasteful number, since it uses less digits than its factorization.

20313123021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2257013675 (or 2257013672 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

Adding to 20313123021 its reverse (12032131302), we get a palindrome (32345254323).

The spelling of 20313123021 in words is "twenty billion, three hundred thirteen million, one hundred twenty-three thousand, twenty-one".