19388793981 has 16 divisors (see below), whose sum is σ = 27380135808. Its totient is φ = 12162086400.

The previous prime is 19388793973. The next prime is 19388794043. The reversal of 19388793981 is 18939788391.

It is not a de Polignac number, because 19388793981 - 2³ = 19388793973 is a prime.

It is a super-2 number, since 2×19388793981² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19388793961) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 135441 + ... + 239001.

It is an arithmetic number, because the mean of its divisors is an integer number (1711258488).

Almost surely, 2^19388793981 is an apocalyptic number.

It is an amenable number.

19388793981 is a deficient number, since it is larger than the sum of its proper divisors (7991341827).

19388793981 is a wasteful number, since it uses less digits than its factorization.

19388793981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107252.

The product of its digits is 23514624, while the sum is 66.

The spelling of 19388793981 in words is "nineteen billion, three hundred eighty-eight million, seven hundred ninety-three thousand, nine hundred eighty-one".