19881968 has 10 divisors (see below), whose sum is σ = 38521344. Its totient is φ = 9940976.

The previous prime is 19881947. The next prime is 19881971. The reversal of 19881968 is 86918891.

It is a happy number.

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, 621296 + ... + 621327.

Almost surely, 2^19881968 is an apocalyptic number.

It is an amenable number.

19881968 is a deficient number, since it is larger than the sum of its proper divisors (18639376).

19881968 is a wasteful number, since it uses less digits than its factorization.

19881968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1242631 (or 1242625 counting only the distinct ones).

The product of its digits is 248832, while the sum is 50.

The square root of 19881968 is about 4458.9200486216. The cubic root of 19881968 is about 270.9067275224.

The spelling of 19881968 in words is "nineteen million, eight hundred eighty-one thousand, nine hundred sixty-eight".