851981699 has 2 divisors, whose sum is σ = 851981700. Its totient is φ = 851981698.

The previous prime is 851981657. The next prime is 851981723. The reversal of 851981699 is 996189158.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 851981699 - 2⁸ = 851981443 is a prime.

It is not a weakly prime, because it can be changed into another prime (851981629) 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, 425990849 + 425990850.

It is an arithmetic number, because the mean of its divisors is an integer number (425990850).

Almost surely, 2^851981699 is an apocalyptic number.

851981699 is a deficient number, since it is larger than the sum of its proper divisors (1).

851981699 is an equidigital number, since it uses as much as digits as its factorization.

851981699 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1399680, while the sum is 56.

The square root of 851981699 is about 29188.7255460049. The cubic root of 851981699 is about 948.0038228970.

The spelling of 851981699 in words is "eight hundred fifty-one million, nine hundred eighty-one thousand, six hundred ninety-nine".