851422561 has 4 divisors (see below), whose sum is σ = 928824624. Its totient is φ = 774020500.

The previous prime is 851422553. The next prime is 851422573. The reversal of 851422561 is 165224158.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 851422561 - 2³ = 851422553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (851422541) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38701015 + ... + 38701036.

It is an arithmetic number, because the mean of its divisors is an integer number (232206156).

Almost surely, 2^851422561 is an apocalyptic number.

It is an amenable number.

851422561 is a deficient number, since it is larger than the sum of its proper divisors (77402063).

851422561 is a wasteful number, since it uses less digits than its factorization.

851422561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77402062.

The product of its digits is 19200, while the sum is 34.

The square root of 851422561 is about 29179.1459950424. The cubic root of 851422561 is about 947.7963924004.

The spelling of 851422561 in words is "eight hundred fifty-one million, four hundred twenty-two thousand, five hundred sixty-one".