851765911901 has 2 divisors, whose sum is σ = 851765911902. Its totient is φ = 851765911900.

The previous prime is 851765911883. The next prime is 851765912071. The reversal of 851765911901 is 109119567158.

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., 510124492900 + 341641419001 = 714230^2 + 584501^2 .

It is a cyclic number.

It is not a de Polignac number, because 851765911901 - 2⁶ = 851765911837 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (851765911301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 425882955950 + 425882955951.

It is an arithmetic number, because the mean of its divisors is an integer number (425882955951).

Almost surely, 2^851765911901 is an apocalyptic number.

It is an amenable number.

851765911901 is a deficient number, since it is larger than the sum of its proper divisors (1).

851765911901 is an equidigital number, since it uses as much as digits as its factorization.

851765911901 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 680400, while the sum is 53.

The spelling of 851765911901 in words is "eight hundred fifty-one billion, seven hundred sixty-five million, nine hundred eleven thousand, nine hundred one".