31311993 has 8 divisors (see below), whose sum is σ = 43564608. Its totient is φ = 19967024.

The previous prime is 31311989. The next prime is 31311997. The reversal of 31311993 is 39911313.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (31311989) and next prime (31311997).

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 31311993 - 2² = 31311989 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 31311993.

It is not an unprimeable number, because it can be changed into a prime (31311997) 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, 226830 + ... + 226967.

It is an arithmetic number, because the mean of its divisors is an integer number (5445576).

Almost surely, 2^31311993 is an apocalyptic number.

It is an amenable number.

31311993 is a deficient number, since it is larger than the sum of its proper divisors (12252615).

31311993 is a wasteful number, since it uses less digits than its factorization.

31311993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 453823.

The product of its digits is 2187, while the sum is 30.

The square root of 31311993 is about 5595.7120190374. The cubic root of 31311993 is about 315.1884083245.

The spelling of 31311993 in words is "thirty-one million, three hundred eleven thousand, nine hundred ninety-three".