31212144520 has 32 divisors (see below), whose sum is σ = 70698663000. Its totient is φ = 12401064448.

The previous prime is 31212144463. The next prime is 31212144529. The reversal of 31212144520 is 2544121213.

It can be written as a sum of positive squares in 4 ways, for example, as 7845353476 + 23366791044 = 88574^2 + 152862^2 .

It is not an unprimeable number, because it can be changed into a prime (31212144529) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2612509 + ... + 2624428.

Almost surely, 2^31212144520 is an apocalyptic number.

It is an amenable number.

31212144520 is an abundant number, since it is smaller than the sum of its proper divisors (39486518480).

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

31212144520 is a wasteful number, since it uses less digits than its factorization.

31212144520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5237097 (or 5237093 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 25.

Adding to 31212144520 its reverse (2544121213), we get a palindrome (33756265733).

The spelling of 31212144520 in words is "thirty-one billion, two hundred twelve million, one hundred forty-four thousand, five hundred twenty".