19968881 has 4 divisors (see below), whose sum is σ = 20266992. Its totient is φ = 19670772.

The previous prime is 19968877. The next prime is 19968889. The reversal of 19968881 is 18886991.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18886991 = 2237 ⋅8443.

It is a cyclic number.

It is not a de Polignac number, because 19968881 - 2² = 19968877 is a prime.

It is a super-2 number, since 2×19968881² = 797512416784322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19968889) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 148955 + ... + 149088.

It is an arithmetic number, because the mean of its divisors is an integer number (5066748).

Almost surely, 2^19968881 is an apocalyptic number.

It is an amenable number.

19968881 is a deficient number, since it is larger than the sum of its proper divisors (298111).

19968881 is an equidigital number, since it uses as much as digits as its factorization.

19968881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 298110.

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

The square root of 19968881 is about 4468.6553906069. The cubic root of 19968881 is about 271.3009053094.

The spelling of 19968881 in words is "nineteen million, nine hundred sixty-eight thousand, eight hundred eighty-one".