31212040321 has 32 divisors (see below), whose sum is σ = 39120768000. Its totient is φ = 24192043200.

The previous prime is 31212040289. The next prime is 31212040351. The reversal of 31212040321 is 12304021213.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 31212040321 - 2⁵ = 31212040289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31212040351) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13331611 + ... + 13333951.

It is an arithmetic number, because the mean of its divisors is an integer number (1222524000).

Almost surely, 2^31212040321 is an apocalyptic number.

It is an amenable number.

31212040321 is a deficient number, since it is larger than the sum of its proper divisors (7908727679).

31212040321 is a wasteful number, since it uses less digits than its factorization.

31212040321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3205.

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

Adding to 31212040321 its reverse (12304021213), we get a palindrome (43516061534).

The spelling of 31212040321 in words is "thirty-one billion, two hundred twelve million, forty thousand, three hundred twenty-one".