31145857 has 2 divisors, whose sum is σ = 31145858. Its totient is φ = 31145856.

The previous prime is 31145839. The next prime is 31145867. The reversal of 31145857 is 75854113.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25040016 + 6105841 = 5004^2 + 2471^2 .

It is a cyclic number.

It is not a de Polignac number, because 31145857 - 2⁷ = 31145729 is a prime.

It is equal to p_1924396 and since 31145857 and 1924396 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (31145867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15572928 + 15572929.

It is an arithmetic number, because the mean of its divisors is an integer number (15572929).

Almost surely, 2^31145857 is an apocalyptic number.

It is an amenable number.

31145857 is a deficient number, since it is larger than the sum of its proper divisors (1).

31145857 is an equidigital number, since it uses as much as digits as its factorization.

31145857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 16800, while the sum is 34.

The square root of 31145857 is about 5580.8473370986. The cubic root of 31145857 is about 314.6299745102.

The spelling of 31145857 in words is "thirty-one million, one hundred forty-five thousand, eight hundred fifty-seven".