856648490666 has 16 divisors (see below), whose sum is σ = 1316406567168. Its totient is φ = 417847778400.

The previous prime is 856648490653. The next prime is 856648490671. The reversal of 856648490666 is 666094846658.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 856648490596 and 856648490605.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 821381 + ... + 1545303.

It is an arithmetic number, because the mean of its divisors is an integer number (82275410448).

Almost surely, 2^856648490666 is an apocalyptic number.

856648490666 is a deficient number, since it is larger than the sum of its proper divisors (459758076502).

856648490666 is a wasteful number, since it uses less digits than its factorization.

856648490666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 738397.

The product of its (nonzero) digits is 358318080, while the sum is 68.

The spelling of 856648490666 in words is "eight hundred fifty-six billion, six hundred forty-eight million, four hundred ninety thousand, six hundred sixty-six".