19881969 has 8 divisors (see below), whose sum is σ = 26574240. Its totient is φ = 13222176.

The previous prime is 19881947. The next prime is 19881971. The reversal of 19881969 is 96918891.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 19881969 - 2⁹ = 19881457 is a prime.

It is a super-2 number, since 2×19881969² = 790585382633922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (19881929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6652 + ... + 9165.

It is an arithmetic number, because the mean of its divisors is an integer number (3321780).

Almost surely, 2^19881969 is an apocalyptic number.

It is an amenable number.

19881969 is a deficient number, since it is larger than the sum of its proper divisors (6692271).

19881969 is a wasteful number, since it uses less digits than its factorization.

19881969 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16239.

The product of its digits is 279936, while the sum is 51.

The square root of 19881969 is about 4458.9201607564. The cubic root of 19881969 is about 270.9067320643.

The spelling of 19881969 in words is "nineteen million, eight hundred eighty-one thousand, nine hundred sixty-nine".