85317979 has 2 divisors, whose sum is σ = 85317980. Its totient is φ = 85317978.

The previous prime is 85317937. The next prime is 85317997. The reversal of 85317979 is 97971358.

Together with next prime (85317997) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 85317979 - 2⁷ = 85317851 is a prime.

It is not a weakly prime, because it can be changed into another prime (85317919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42658989 + 42658990.

It is an arithmetic number, because the mean of its divisors is an integer number (42658990).

Almost surely, 2^85317979 is an apocalyptic number.

85317979 is a deficient number, since it is larger than the sum of its proper divisors (1).

85317979 is an equidigital number, since it uses as much as digits as its factorization.

85317979 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 476280, while the sum is 49.

The square root of 85317979 is about 9236.7731919756. The cubic root of 85317979 is about 440.2305592626.

The spelling of 85317979 in words is "eighty-five million, three hundred seventeen thousand, nine hundred seventy-nine".