85631257 has 2 divisors, whose sum is σ = 85631258. Its totient is φ = 85631256.

The previous prime is 85631239. The next prime is 85631279. The reversal of 85631257 is 75213658.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 85082176 + 549081 = 9224^2 + 741^2 .

It is a cyclic number.

It is not a de Polignac number, because 85631257 - 2¹¹ = 85629209 is a prime.

It is not a weakly prime, because it can be changed into another prime (85631237) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42815628 + 42815629.

It is an arithmetic number, because the mean of its divisors is an integer number (42815629).

Almost surely, 2^85631257 is an apocalyptic number.

It is an amenable number.

85631257 is a deficient number, since it is larger than the sum of its proper divisors (1).

85631257 is an equidigital number, since it uses as much as digits as its factorization.

85631257 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 50400, while the sum is 37.

The square root of 85631257 is about 9253.7158482417. The cubic root of 85631257 is about 440.7687267628.

The spelling of 85631257 in words is "eighty-five million, six hundred thirty-one thousand, two hundred fifty-seven".