856690 has 8 divisors (see below), whose sum is σ = 1542060. Its totient is φ = 342672.

The previous prime is 856649. The next prime is 856693. The reversal of 856690 is 96658.

It can be written as a sum of positive squares in 2 ways, for example, as 851929 + 4761 = 923^2 + 69^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×856690² = 1467835512200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (856693) 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, 42825 + ... + 42844.

2⁸⁵⁶⁶⁹⁰ is an apocalyptic number.

856690 is a deficient number, since it is larger than the sum of its proper divisors (685370).

856690 is a wasteful number, since it uses less digits than its factorization.

856690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85676.

The product of its (nonzero) digits is 12960, while the sum is 34.

The square root of 856690 is about 925.5754966506. The cubic root of 856690 is about 94.9746931668.

The spelling of 856690 in words is "eight hundred fifty-six thousand, six hundred ninety".