19491000056 has 16 divisors (see below), whose sum is σ = 39867954840. Its totient is φ = 8859545440.

The previous prime is 19491000049. The next prime is 19491000077. The reversal of 19491000056 is 65000019491.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 110744231 + ... + 110744406.

Almost surely, 2^19491000056 is an apocalyptic number.

It is an amenable number.

19491000056 is an abundant number, since it is smaller than the sum of its proper divisors (20376954784).

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

19491000056 is a wasteful number, since it uses less digits than its factorization.

19491000056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221488654 (or 221488650 counting only the distinct ones).

The product of its (nonzero) digits is 9720, while the sum is 35.

The spelling of 19491000056 in words is "nineteen billion, four hundred ninety-one million, fifty-six", and thus it is an aban number.