85257779 has 2 divisors, whose sum is σ = 85257780. Its totient is φ = 85257778.

The previous prime is 85257727. The next prime is 85257791. The reversal of 85257779 is 97775258.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 85257779 - 2¹² = 85253683 is a prime.

It is not a weakly prime, because it can be changed into another prime (85257379) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42628889 + 42628890.

It is an arithmetic number, because the mean of its divisors is an integer number (42628890).

Almost surely, 2^85257779 is an apocalyptic number.

85257779 is a deficient number, since it is larger than the sum of its proper divisors (1).

85257779 is an equidigital number, since it uses as much as digits as its factorization.

85257779 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1234800, while the sum is 50.

The square root of 85257779 is about 9233.5139031682. The cubic root of 85257779 is about 440.1269933022.

The spelling of 85257779 in words is "eighty-five million, two hundred fifty-seven thousand, seven hundred seventy-nine".