851786993 has 2 divisors, whose sum is σ = 851786994. Its totient is φ = 851786992.

The previous prime is 851786983. The next prime is 851787029. The reversal of 851786993 is 399687158.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 750321664 + 101465329 = 27392^2 + 10073^2 .

It is a cyclic number.

It is not a de Polignac number, because 851786993 - 2¹⁶ = 851721457 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (851786933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 425893496 + 425893497.

It is an arithmetic number, because the mean of its divisors is an integer number (425893497).

Almost surely, 2^851786993 is an apocalyptic number.

It is an amenable number.

851786993 is a deficient number, since it is larger than the sum of its proper divisors (1).

851786993 is an equidigital number, since it uses as much as digits as its factorization.

851786993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3265920, while the sum is 56.

The square root of 851786993 is about 29185.3900607821. The cubic root of 851786993 is about 947.9316006511.

The spelling of 851786993 in words is "eight hundred fifty-one million, seven hundred eighty-six thousand, nine hundred ninety-three".