856164261 has 4 divisors (see below), whose sum is σ = 1141552352. Its totient is φ = 570776172.

The previous prime is 856164229. The next prime is 856164299. The reversal of 856164261 is 162461658.

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 856164261 - 2⁵ = 856164229 is a prime.

It is a super-2 number, since 2×856164261² = 1466034483627352242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (856164161) 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, 142694041 + ... + 142694046.

It is an arithmetic number, because the mean of its divisors is an integer number (285388088).

Almost surely, 2^856164261 is an apocalyptic number.

It is an amenable number.

856164261 is a deficient number, since it is larger than the sum of its proper divisors (285388091).

856164261 is a wasteful number, since it uses less digits than its factorization.

856164261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 285388090.

The product of its digits is 69120, while the sum is 39.

The square root of 856164261 is about 29260.2847046983. The cubic root of 856164261 is about 949.5526096543.

The spelling of 856164261 in words is "eight hundred fifty-six million, one hundred sixty-four thousand, two hundred sixty-one".