851168221 has 2 divisors, whose sum is σ = 851168222. Its totient is φ = 851168220.

The previous prime is 851168119. The next prime is 851168243. The reversal of 851168221 is 122861158.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 506880196 + 344288025 = 22514^2 + 18555^2 .

It is a cyclic number.

It is not a de Polignac number, because 851168221 - 2²⁵ = 817613789 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (851168281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 425584110 + 425584111.

It is an arithmetic number, because the mean of its divisors is an integer number (425584111).

Almost surely, 2^851168221 is an apocalyptic number.

It is an amenable number.

851168221 is a deficient number, since it is larger than the sum of its proper divisors (1).

851168221 is an equidigital number, since it uses as much as digits as its factorization.

851168221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7680, while the sum is 34.

The square root of 851168221 is about 29174.7874199625. The cubic root of 851168221 is about 947.7020066225.

The spelling of 851168221 in words is "eight hundred fifty-one million, one hundred sixty-eight thousand, two hundred twenty-one".