31742857 has 2 divisors, whose sum is σ = 31742858. Its totient is φ = 31742856.

The previous prime is 31742831. The next prime is 31742881. The reversal of 31742857 is 75824713.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 31539456 + 203401 = 5616^2 + 451^2 .

It is an emirp because it is prime and its reverse (75824713) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31742857 - 2¹⁵ = 31710089 is a prime.

It is not a weakly prime, because it can be changed into another prime (31742827) by changing a digit.

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

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15871428 + 15871429.

It is an arithmetic number, because the mean of its divisors is an integer number (15871429).

Almost surely, 2^31742857 is an apocalyptic number.

It is an amenable number.

31742857 is a deficient number, since it is larger than the sum of its proper divisors (1).

31742857 is an equidigital number, since it uses as much as digits as its factorization.

31742857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 47040, while the sum is 37.

The square root of 31742857 is about 5634.0799603839. The cubic root of 31742857 is about 316.6275284347.

The spelling of 31742857 in words is "thirty-one million, seven hundred forty-two thousand, eight hundred fifty-seven".