85021691 has 2 divisors, whose sum is σ = 85021692. Its totient is φ = 85021690.

The previous prime is 85021681. The next prime is 85021697. The reversal of 85021691 is 19612058.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 85021691 - 2⁶ = 85021627 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (85021697) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42510845 + 42510846.

It is an arithmetic number, because the mean of its divisors is an integer number (42510846).

Almost surely, 2^85021691 is an apocalyptic number.

85021691 is a deficient number, since it is larger than the sum of its proper divisors (1).

85021691 is an equidigital number, since it uses as much as digits as its factorization.

85021691 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4320, while the sum is 32.

The square root of 85021691 is about 9220.7207418943. The cubic root of 85021691 is about 439.7203646750.

The spelling of 85021691 in words is "eighty-five million, twenty-one thousand, six hundred ninety-one".