85779191 has 2 divisors, whose sum is σ = 85779192. Its totient is φ = 85779190.

The previous prime is 85779157. The next prime is 85779223. The reversal of 85779191 is 19197758.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-85779191 is a prime.

It is a super-2 number, since 2×85779191² = 14716139217228962, which contains 22 as substring.

It is a Chen prime.

It is a plaindrome in base 12.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85779131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42889595 + 42889596.

It is an arithmetic number, because the mean of its divisors is an integer number (42889596).

Almost surely, 2^85779191 is an apocalyptic number.

85779191 is a deficient number, since it is larger than the sum of its proper divisors (1).

85779191 is an equidigital number, since it uses as much as digits as its factorization.

85779191 is an evil number, because the sum of its binary digits is even.

The product of its digits is 158760, while the sum is 47.

The square root of 85779191 is about 9261.7056204567. The cubic root of 85779191 is about 441.0224003650.

The spelling of 85779191 in words is "eighty-five million, seven hundred seventy-nine thousand, one hundred ninety-one".