31231313321 has 8 divisors (see below), whose sum is σ = 33635146440. Its totient is φ = 28827683712.

The previous prime is 31231313297. The next prime is 31231313357. The reversal of 31231313321 is 12331313213.

It can be written as a sum of positive squares in 4 ways, for example, as 11122655296 + 20108658025 = 105464^2 + 141805^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 31231313321 - 2¹⁸ = 31231051177 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (31231313371) 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, 452045 + ... + 516533.

It is an arithmetic number, because the mean of its divisors is an integer number (4204393305).

Almost surely, 2^31231313321 is an apocalyptic number.

It is an amenable number.

31231313321 is a deficient number, since it is larger than the sum of its proper divisors (2403833119).

31231313321 is a wasteful number, since it uses less digits than its factorization.

31231313321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101755.

The product of its digits is 972, while the sum is 23.

Adding to 31231313321 its reverse (12331313213), we get a palindrome (43562626534).

The spelling of 31231313321 in words is "thirty-one billion, two hundred thirty-one million, three hundred thirteen thousand, three hundred twenty-one".