21310023020 has 192 divisors, whose sum is σ = 56757335040. Its totient is φ = 6605491200.

The previous prime is 21310022969. The next prime is 21310023113. The reversal of 21310023020 is 2032001312.

It is a happy number.

It is a super-2 number, since 2×21310023020² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21310022986 and 21310023004.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1902035 + ... + 1913205.

It is an arithmetic number, because the mean of its divisors is an integer number (295611120).

Almost surely, 2^21310023020 is an apocalyptic number.

21310023020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21310023020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28378667520).

21310023020 is an abundant number, since it is smaller than the sum of its proper divisors (35447312020).

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

21310023020 is a wasteful number, since it uses less digits than its factorization.

21310023020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11256 (or 11254 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 14.

Adding to 21310023020 its reverse (2032001312), we get a palindrome (23342024332).

The spelling of 21310023020 in words is "twenty-one billion, three hundred ten million, twenty-three thousand, twenty".