85191851 has 2 divisors, whose sum is σ = 85191852. Its totient is φ = 85191850.

The previous prime is 85191823. The next prime is 85191853. The reversal of 85191851 is 15819158.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-85191851 is a prime.

Together with 85191853, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (85191853) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42595925 + 42595926.

It is an arithmetic number, because the mean of its divisors is an integer number (42595926).

Almost surely, 2^85191851 is an apocalyptic number.

85191851 is a deficient number, since it is larger than the sum of its proper divisors (1).

85191851 is an equidigital number, since it uses as much as digits as its factorization.

85191851 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 14400, while the sum is 38.

The square root of 85191851 is about 9229.9431742563. The cubic root of 85191851 is about 440.0135171467.

The spelling of 85191851 in words is "eighty-five million, one hundred ninety-one thousand, eight hundred fifty-one".