31199897 has 4 divisors (see below), whose sum is σ = 31925520. Its totient is φ = 30474276.

The previous prime is 31199887. The next prime is 31199899. The reversal of 31199897 is 79899113.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31199897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31199899) 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, 362747 + ... + 362832.

It is an arithmetic number, because the mean of its divisors is an integer number (7981380).

Almost surely, 2^31199897 is an apocalyptic number.

It is an amenable number.

31199897 is a deficient number, since it is larger than the sum of its proper divisors (725623).

31199897 is an equidigital number, since it uses as much as digits as its factorization.

31199897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 725622.

The product of its digits is 122472, while the sum is 47.

The square root of 31199897 is about 5585.6867975210. The cubic root of 31199897 is about 314.8118368980.

The spelling of 31199897 in words is "thirty-one million, one hundred ninety-nine thousand, eight hundred ninety-seven".