21031013310 has 128 divisors (see below), whose sum is σ = 54757638144. Its totient is φ = 5149992960.

The previous prime is 21031013291. The next prime is 21031013317. The reversal of 21031013310 is 1331013012.

It is a super-2 number, since 2×21031013310² (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 Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21031013310.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21031013317) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3948309 + ... + 3953631.

It is an arithmetic number, because the mean of its divisors is an integer number (427794048).

Almost surely, 2^21031013310 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21031013310, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27378819072).

21031013310 is an abundant number, since it is smaller than the sum of its proper divisors (33726624834).

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

21031013310 is a wasteful number, since it uses less digits than its factorization.

21031013310 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5538.

The product of its (nonzero) digits is 54, while the sum is 15.

Adding to 21031013310 its reverse (1331013012), we get a palindrome (22362026322).

The spelling of 21031013310 in words is "twenty-one billion, thirty-one million, thirteen thousand, three hundred ten".