851918489 has 2 divisors, whose sum is σ = 851918490. Its totient is φ = 851918488.

The previous prime is 851918477. The next prime is 851918513. The reversal of 851918489 is 984819158.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 849139600 + 2778889 = 29140^2 + 1667^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-851918489 is a prime.

It is a super-2 number, since 2×851918489² = 1451530223800086242, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 851918489.

It is not a weakly prime, because it can be changed into another prime (851968489) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 425959244 + 425959245.

It is an arithmetic number, because the mean of its divisors is an integer number (425959245).

Almost surely, 2^851918489 is an apocalyptic number.

It is an amenable number.

851918489 is a deficient number, since it is larger than the sum of its proper divisors (1).

851918489 is an equidigital number, since it uses as much as digits as its factorization.

851918489 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 829440, while the sum is 53.

The square root of 851918489 is about 29187.6427448330. The cubic root of 851918489 is about 947.9803776345.

The spelling of 851918489 in words is "eight hundred fifty-one million, nine hundred eighteen thousand, four hundred eighty-nine".