31221220022 has 4 divisors (see below), whose sum is σ = 46831830036. Its totient is φ = 15610610010.

The previous prime is 31221220007. The next prime is 31221220057. The reversal of 31221220022 is 22002212213.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7805305004 + ... + 7805305007.

It is an arithmetic number, because the mean of its divisors is an integer number (11707957509).

Almost surely, 2^31221220022 is an apocalyptic number.

31221220022 is a deficient number, since it is larger than the sum of its proper divisors (15610610014).

31221220022 is a wasteful number, since it uses less digits than its factorization.

31221220022 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15610610013.

The product of its (nonzero) digits is 192, while the sum is 17.

Adding to 31221220022 its reverse (22002212213), we get a palindrome (53223432235).

The spelling of 31221220022 in words is "thirty-one billion, two hundred twenty-one million, two hundred twenty thousand, twenty-two".