812779622161 has 16 divisors (see below), whose sum is σ = 889706680128. Its totient is φ = 737912059200.

The previous prime is 812779622101. The next prime is 812779622173. The reversal of 812779622161 is 161226977218.

It is a cyclic number.

It is not a de Polignac number, because 812779622161 - 2⁷ = 812779622033 is a prime.

It is a super-2 number, since 2×812779622161² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 812779622099 and 812779622108.

It is not an unprimeable number, because it can be changed into a prime (812779622101) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21476946 + ... + 21514756.

It is an arithmetic number, because the mean of its divisors is an integer number (55606667508).

Almost surely, 2^812779622161 is an apocalyptic number.

It is an amenable number.

812779622161 is a deficient number, since it is larger than the sum of its proper divisors (76927057967).

812779622161 is a wasteful number, since it uses less digits than its factorization.

812779622161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64992.

The product of its digits is 1016064, while the sum is 52.

The spelling of 812779622161 in words is "eight hundred twelve billion, seven hundred seventy-nine million, six hundred twenty-two thousand, one hundred sixty-one".