19808936640 has 112 divisors (see below), whose sum is σ = 69881556960. Its totient is φ = 5282380800.

The previous prime is 19808936627. The next prime is 19808936663. The reversal of 19808936640 is 4663980891.

It is a super-3 number, since 3×19808936640³ (a number of 32 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1137711 + ... + 1154990.

Almost surely, 2^19808936640 is an apocalyptic number.

19808936640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19808936640 is an abundant number, since it is smaller than the sum of its proper divisors (50072620320).

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

19808936640 is a wasteful number, since it uses less digits than its factorization.

19808936640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2292727 (or 2292711 counting only the distinct ones).

The product of its (nonzero) digits is 2239488, while the sum is 54.

The spelling of 19808936640 in words is "nineteen billion, eight hundred eight million, nine hundred thirty-six thousand, six hundred forty".