19818086408 has 8 divisors (see below), whose sum is σ = 37158912030. Its totient is φ = 9909043200.

The previous prime is 19818086399. The next prime is 19818086419. The reversal of 19818086408 is 80468081891.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 13165726564 + 6652359844 = 114742^2 + 81562^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a self number, because there is not a number n which added to its sum of digits gives 19818086408.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1238630393 + ... + 1238630408.

Almost surely, 2^19818086408 is an apocalyptic number.

It is an amenable number.

19818086408 is a deficient number, since it is larger than the sum of its proper divisors (17340825622).

19818086408 is a wasteful number, since it uses less digits than its factorization.

19818086408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2477260807 (or 2477260803 counting only the distinct ones).

The product of its (nonzero) digits is 884736, while the sum is 53.

The spelling of 19818086408 in words is "nineteen billion, eight hundred eighteen million, eighty-six thousand, four hundred eight".