31279897 has 4 divisors (see below), whose sum is σ = 34123536. Its totient is φ = 28436260.

The previous prime is 31279889. The next prime is 31279903. The reversal of 31279897 is 79897213.

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, and also an emirpimes, since its reverse is a distinct semiprime: 79897213 = 11 ⋅7263383.

It is a cyclic number.

It is not a de Polignac number, because 31279897 - 2³ = 31279889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31279867) 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, 1421803 + ... + 1421824.

It is an arithmetic number, because the mean of its divisors is an integer number (8530884).

Almost surely, 2^31279897 is an apocalyptic number.

It is an amenable number.

31279897 is a deficient number, since it is larger than the sum of its proper divisors (2843639).

31279897 is a wasteful number, since it uses less digits than its factorization.

31279897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2843638.

The product of its digits is 190512, while the sum is 46.

The square root of 31279897 is about 5592.8433734550. The cubic root of 31279897 is about 315.0806780835.

The spelling of 31279897 in words is "thirty-one million, two hundred seventy-nine thousand, eight hundred ninety-seven".