97831931 has 4 divisors (see below), whose sum is σ = 102981000. Its totient is φ = 92682864.

The previous prime is 97831907. The next prime is 97831967. The reversal of 97831931 is 13913879.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13913879 = 7 ⋅1987697.

It is a cyclic number.

It is not a de Polignac number, because 97831931 - 2¹⁰ = 97830907 is a prime.

It is a super-2 number, since 2×97831931² = 19142173446377522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (97831901) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2574506 + ... + 2574543.

It is an arithmetic number, because the mean of its divisors is an integer number (25745250).

Almost surely, 2^97831931 is an apocalyptic number.

97831931 is a deficient number, since it is larger than the sum of its proper divisors (5149069).

97831931 is a wasteful number, since it uses less digits than its factorization.

97831931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5149068.

The product of its digits is 40824, while the sum is 41.

The square root of 97831931 is about 9891.0025275500. The cubic root of 97831931 is about 460.7799166871.

The spelling of 97831931 in words is "ninety-seven million, eight hundred thirty-one thousand, nine hundred thirty-one".