85218919 has 2 divisors, whose sum is σ = 85218920. Its totient is φ = 85218918.

The previous prime is 85218901. The next prime is 85218923. The reversal of 85218919 is 91981258.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-85218919 is a prime.

It is a super-2 number, since 2×85218919² = 14524528311057122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85218989) 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, 42609459 + 42609460.

It is an arithmetic number, because the mean of its divisors is an integer number (42609460).

Almost surely, 2^85218919 is an apocalyptic number.

85218919 is a deficient number, since it is larger than the sum of its proper divisors (1).

85218919 is an equidigital number, since it uses as much as digits as its factorization.

85218919 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 51840, while the sum is 43.

The square root of 85218919 is about 9231.4093723548. The cubic root of 85218919 is about 440.0601140319.

The spelling of 85218919 in words is "eighty-five million, two hundred eighteen thousand, nine hundred nineteen".