851691361 has 2 divisors, whose sum is σ = 851691362. Its totient is φ = 851691360.

The previous prime is 851691307. The next prime is 851691383. The reversal of 851691361 is 163196158.

851691361 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 572166400 + 279524961 = 23920^2 + 16719^2 .

It is a cyclic number.

It is not a de Polignac number, because 851691361 - 2⁷ = 851691233 is a prime.

It is not a weakly prime, because it can be changed into another prime (851691661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 425845680 + 425845681.

It is an arithmetic number, because the mean of its divisors is an integer number (425845681).

Almost surely, 2^851691361 is an apocalyptic number.

It is an amenable number.

851691361 is a deficient number, since it is larger than the sum of its proper divisors (1).

851691361 is an equidigital number, since it uses as much as digits as its factorization.

851691361 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 38880, while the sum is 40.

The square root of 851691361 is about 29183.7516608129. The cubic root of 851691361 is about 947.8961238679.

The spelling of 851691361 in words is "eight hundred fifty-one million, six hundred ninety-one thousand, three hundred sixty-one".