31137997 has 8 divisors (see below), whose sum is σ = 34306272. Its totient is φ = 28026000.

The previous prime is 31137991. The next prime is 31138001. The reversal of 31137997 is 79973113.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31137997 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31137991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is an upside-down number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12903 + ... + 15124.

It is an arithmetic number, because the mean of its divisors is an integer number (4288284).

Almost surely, 2^31137997 is an apocalyptic number.

It is an amenable number.

31137997 is a deficient number, since it is larger than the sum of its proper divisors (3168275).

31137997 is a wasteful number, since it uses less digits than its factorization.

31137997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28139.

The product of its digits is 35721, while the sum is 40.

The square root of 31137997 is about 5580.1430985235. The cubic root of 31137997 is about 314.6035055039.

The spelling of 31137997 in words is "thirty-one million, one hundred thirty-seven thousand, nine hundred ninety-seven".