21656086670594 has 24 divisors (see below), whose sum is σ = 34680398538240. Its totient is φ = 10136891609768.

The previous prime is 21656086670573. The next prime is 21656086670627. The reversal of 21656086670594 is 49507668065612.

It is a happy number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21656086670594.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 217704434 + ... + 217803885.

It is an arithmetic number, because the mean of its divisors is an integer number (1445016605760).

Almost surely, 2^{21656086670594} is an apocalyptic number.

21656086670594 is a deficient number, since it is larger than the sum of its proper divisors (13024311867646).

21656086670594 is a wasteful number, since it uses less digits than its factorization.

21656086670594 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 435508414 (or 435508391 counting only the distinct ones).

The product of its (nonzero) digits is 130636800, while the sum is 65.

The spelling of 21656086670594 in words is "twenty-one trillion, six hundred fifty-six billion, eighty-six million, six hundred seventy thousand, five hundred ninety-four".