21013112310 has 64 divisors (see below), whose sum is σ = 53651372544. Its totient is φ = 5248857600.

The previous prime is 21013112249. The next prime is 21013112353. The reversal of 21013112310 is 1321131012.

It is a happy number.

It is a super-2 number, since 2×21013112310² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21013112310.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9975 + ... + 205245.

It is an arithmetic number, because the mean of its divisors is an integer number (838302696).

Almost surely, 2^21013112310 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21013112310, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26825686272).

21013112310 is an abundant number, since it is smaller than the sum of its proper divisors (32638260234).

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

21013112310 is a wasteful number, since it uses less digits than its factorization.

21013112310 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195509.

The product of its (nonzero) digits is 36, while the sum is 15.

Adding to 21013112310 its reverse (1321131012), we get a palindrome (22334243322).

The spelling of 21013112310 in words is "twenty-one billion, thirteen million, one hundred twelve thousand, three hundred ten".