21313112020 has 24 divisors (see below), whose sum is σ = 44795102184. Its totient is φ = 8518089216.

The previous prime is 21313111979. The next prime is 21313112053. The reversal of 21313112020 is 2021131312.

It can be written as a sum of positive squares in 4 ways, for example, as 6444236176 + 14868875844 = 80276^2 + 121938^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21313111985 and 21313112003.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 422769 + ... + 470488.

It is an arithmetic number, because the mean of its divisors is an integer number (1866462591).

Almost surely, 2^21313112020 is an apocalyptic number.

21313112020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21313112020 is an abundant number, since it is smaller than the sum of its proper divisors (23481990164).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21313112020 is a wasteful number, since it uses less digits than its factorization.

21313112020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 894459 (or 894457 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 21313112020 its reverse (2021131312), we get a palindrome (23334243332).

The spelling of 21313112020 in words is "twenty-one billion, three hundred thirteen million, one hundred twelve thousand, twenty".