31031312321 has 8 divisors (see below), whose sum is σ = 32908765824. Its totient is φ = 29159645760.

The previous prime is 31031312303. The next prime is 31031312381. The reversal of 31031312321 is 12321313013.

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

It is not a de Polignac number, because 31031312321 - 2¹⁴ = 31031295937 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 31031312293 and 31031312302.

It is not an unprimeable number, because it can be changed into a prime (31031312381) 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, 1435685 + ... + 1457138.

It is an arithmetic number, because the mean of its divisors is an integer number (4113595728).

Almost surely, 2^31031312321 is an apocalyptic number.

It is an amenable number.

31031312321 is a deficient number, since it is larger than the sum of its proper divisors (1877453503).

31031312321 is a wasteful number, since it uses less digits than its factorization.

31031312321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2893471.

The product of its (nonzero) digits is 324, while the sum is 20.

Adding to 31031312321 its reverse (12321313013), we get a palindrome (43352625334).

The spelling of 31031312321 in words is "thirty-one billion, thirty-one million, three hundred twelve thousand, three hundred twenty-one".