21121312302 has 40 divisors (see below), whose sum is σ = 47344710600. Its totient is φ = 7037860176.

The previous prime is 21121312283. The next prime is 21121312307. The reversal of 21121312302 is 20321312112.

It is a super-2 number, since 2×21121312302² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121312307) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 448849 + ... + 493667.

It is an arithmetic number, because the mean of its divisors is an integer number (1183617765).

Almost surely, 2^21121312302 is an apocalyptic number.

21121312302 is an abundant number, since it is smaller than the sum of its proper divisors (26223398298).

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

21121312302 is a wasteful number, since it uses less digits than its factorization.

21121312302 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47742 (or 47733 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 21121312302 its reverse (20321312112), we get a palindrome (41442624414).

The spelling of 21121312302 in words is "twenty-one billion, one hundred twenty-one million, three hundred twelve thousand, three hundred two".