856749773 has 4 divisors (see below), whose sum is σ = 934636128. Its totient is φ = 778863420.

The previous prime is 856749769. The next prime is 856749809. The reversal of 856749773 is 377947658.

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 a cyclic number.

It is not a de Polignac number, because 856749773 - 2² = 856749769 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (856749743) 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, 38943161 + ... + 38943182.

It is an arithmetic number, because the mean of its divisors is an integer number (233659032).

Almost surely, 2^856749773 is an apocalyptic number.

It is an amenable number.

856749773 is a deficient number, since it is larger than the sum of its proper divisors (77886355).

856749773 is a wasteful number, since it uses less digits than its factorization.

856749773 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77886354.

The product of its digits is 8890560, while the sum is 56.

The square root of 856749773 is about 29270.2882288508. The cubic root of 856749773 is about 949.7690197450.

The spelling of 856749773 in words is "eight hundred fifty-six million, seven hundred forty-nine thousand, seven hundred seventy-three".