31119997 has 4 divisors (see below), whose sum is σ = 31961116. Its totient is φ = 30278880.

The previous prime is 31119983. The next prime is 31120009. The reversal of 31119997 is 79991113.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 79991113 = 3511 ⋅22783.

It can be written as a sum of positive squares in 2 ways, for example, as 29713401 + 1406596 = 5451^2 + 1186^2 .

It is a cyclic number.

It is not a de Polignac number, because 31119997 - 2¹⁵ = 31087229 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31119947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is an upside-down number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 420504 + ... + 420577.

It is an arithmetic number, because the mean of its divisors is an integer number (7990279).

Almost surely, 2^31119997 is an apocalyptic number.

31119997 is a gapful number since it is divisible by the number (37) formed by its first and last digit.

It is an amenable number.

31119997 is a deficient number, since it is larger than the sum of its proper divisors (841119).

31119997 is an equidigital number, since it uses as much as digits as its factorization.

31119997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 841118.

The product of its digits is 15309, while the sum is 40.

The square root of 31119997 is about 5578.5300035045. The cubic root of 31119997 is about 314.5428726740.

The spelling of 31119997 in words is "thirty-one million, one hundred nineteen thousand, nine hundred ninety-seven".