31213121302 has 32 divisors (see below), whose sum is σ = 53995144320. Its totient is φ = 13383328320.

The previous prime is 31213121287. The next prime is 31213121309. The reversal of 31213121302 is 20312131213.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a self number, because there is not a number n which added to its sum of digits gives 31213121302.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31213121309) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 62848 + ... + 257635.

It is an arithmetic number, because the mean of its divisors is an integer number (1687348260).

Almost surely, 2^31213121302 is an apocalyptic number.

31213121302 is a deficient number, since it is larger than the sum of its proper divisors (22782023018).

31213121302 is a wasteful number, since it uses less digits than its factorization.

31213121302 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 320748.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 31213121302 its reverse (20312131213), we get a palindrome (51525252515).

The spelling of 31213121302 in words is "thirty-one billion, two hundred thirteen million, one hundred twenty-one thousand, three hundred two".