21808814466 has 16 divisors (see below), whose sum is σ = 44796484224. Its totient is φ = 7073128944.

The previous prime is 21808814449. The next prime is 21808814477. The reversal of 21808814466 is 66441880812.

It is a happy number.

It is a Curzon number.

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, 49118730 + ... + 49119173.

It is an arithmetic number, because the mean of its divisors is an integer number (2799780264).

Almost surely, 2^21808814466 is an apocalyptic number.

21808814466 is an abundant number, since it is smaller than the sum of its proper divisors (22987669758).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21808814466 is a wasteful number, since it uses less digits than its factorization.

21808814466 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98237945.

The product of its (nonzero) digits is 589824, while the sum is 48.

The spelling of 21808814466 in words is "twenty-one billion, eight hundred eight million, eight hundred fourteen thousand, four hundred sixty-six".