856136731 has 4 divisors (see below), whose sum is σ = 856697464. Its totient is φ = 855576000.

The previous prime is 856136707. The next prime is 856136737. The reversal of 856136731 is 137631658.

It is a happy number.

856136731 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 856136731 - 2¹⁷ = 856005659 is a prime.

It is a super-2 number, since 2×856136731² = 1465940204334732722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (856136737) 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, 278070 + ... + 281131.

It is an arithmetic number, because the mean of its divisors is an integer number (214174366).

Almost surely, 2^856136731 is an apocalyptic number.

856136731 is a deficient number, since it is larger than the sum of its proper divisors (560733).

856136731 is a wasteful number, since it uses less digits than its factorization.

856136731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 560732.

The product of its digits is 90720, while the sum is 40.

The square root of 856136731 is about 29259.8142680366. The cubic root of 856136731 is about 949.5424319097.

The spelling of 856136731 in words is "eight hundred fifty-six million, one hundred thirty-six thousand, seven hundred thirty-one".