21311031102 has 16 divisors (see below), whose sum is σ = 42708874752. Its totient is φ = 7089208280.

The previous prime is 21311031083. The next prime is 21311031107. The reversal of 21311031102 is 20113011312.

It is a happy number.

It is a super-2 number, since 2×21311031102² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21311031107) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3613998 + ... + 3619889.

It is an arithmetic number, because the mean of its divisors is an integer number (2669304672).

Almost surely, 2^21311031102 is an apocalyptic number.

21311031102 is an abundant number, since it is smaller than the sum of its proper divisors (21397843650).

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

21311031102 is a wasteful number, since it uses less digits than its factorization.

21311031102 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7234383.

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

Adding to 21311031102 its reverse (20113011312), we get a palindrome (41424042414).

The spelling of 21311031102 in words is "twenty-one billion, three hundred eleven million, thirty-one thousand, one hundred two".