19804015664 has 10 divisors (see below), whose sum is σ = 38370280380. Its totient is φ = 9902007824.

The previous prime is 19804015619. The next prime is 19804015681. The reversal of 19804015664 is 46651040891.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 618875474 + ... + 618875505.

It is an arithmetic number, because the mean of its divisors is an integer number (3837028038).

Almost surely, 2^19804015664 is an apocalyptic number.

It is an amenable number.

19804015664 is a deficient number, since it is larger than the sum of its proper divisors (18566264716).

19804015664 is a wasteful number, since it uses less digits than its factorization.

19804015664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1237750987 (or 1237750981 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 44.

The spelling of 19804015664 in words is "nineteen billion, eight hundred four million, fifteen thousand, six hundred sixty-four".