21203131222 has 64 divisors (see below), whose sum is σ = 40159421568. Its totient is φ = 8171136000.

The previous prime is 21203131189. The next prime is 21203131231. The reversal of 21203131222 is 22213130212.

It is a self number, because there is not a number n which added to its sum of digits gives 21203131222.

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, 6124572 + ... + 6128032.

It is an arithmetic number, because the mean of its divisors is an integer number (627490962).

Almost surely, 2^21203131222 is an apocalyptic number.

21203131222 is a deficient number, since it is larger than the sum of its proper divisors (18956290346).

21203131222 is a wasteful number, since it uses less digits than its factorization.

21203131222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4345.

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 21203131222 its reverse (22213130212), we get a palindrome (43416261434).

It can be divided in two parts, 212031 and 31222, that added together give a triangular number (243253 = T₆₉₇).

The spelling of 21203131222 in words is "twenty-one billion, two hundred three million, one hundred thirty-one thousand, two hundred twenty-two".