19971793888 has 12 divisors (see below), whose sum is σ = 39319469280. Its totient is φ = 9985896928.

The previous prime is 19971793823. The next prime is 19971793901. The reversal of 19971793888 is 88839717991.

It is a super-2 number, since 2×19971793888² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 312059248 + ... + 312059311.

It is an arithmetic number, because the mean of its divisors is an integer number (3276622440).

Almost surely, 2^19971793888 is an apocalyptic number.

It is an amenable number.

19971793888 is a deficient number, since it is larger than the sum of its proper divisors (19347675392).

19971793888 is an equidigital number, since it uses as much as digits as its factorization.

19971793888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 624118569 (or 624118561 counting only the distinct ones).

The product of its digits is 54867456, while the sum is 70.

The spelling of 19971793888 in words is "nineteen billion, nine hundred seventy-one million, seven hundred ninety-three thousand, eight hundred eighty-eight".