21031131202 has 4 divisors (see below), whose sum is σ = 31546696806. Its totient is φ = 10515565600.

The previous prime is 21031131169. The next prime is 21031131203. The reversal of 21031131202 is 20213113012.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 18431049121 + 2600082081 = 135761^2 + 50991^2 .

It is not an unprimeable number, because it can be changed into a prime (21031131203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5257782799 + ... + 5257782802.

Almost surely, 2^21031131202 is an apocalyptic number.

21031131202 is a deficient number, since it is larger than the sum of its proper divisors (10515565604).

21031131202 is a wasteful number, since it uses less digits than its factorization.

21031131202 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10515565603.

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 21031131202 its reverse (20213113012), we get a palindrome (41244244214).

The spelling of 21031131202 in words is "twenty-one billion, thirty-one million, one hundred thirty-one thousand, two hundred two".