19881986 has 8 divisors (see below), whose sum is σ = 30182544. Its totient is φ = 9821140.

The previous prime is 19881973. The next prime is 19882003. The reversal of 19881986 is 68918891.

It is a happy number.

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 59720 + ... + 60051.

It is an arithmetic number, because the mean of its divisors is an integer number (3772818).

Almost surely, 2^19881986 is an apocalyptic number.

19881986 is a deficient number, since it is larger than the sum of its proper divisors (10300558).

19881986 is a wasteful number, since it uses less digits than its factorization.

19881986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 119856.

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

The square root of 19881986 is about 4458.9220670471. The cubic root of 19881986 is about 270.9068092768.

The spelling of 19881986 in words is "nineteen million, eight hundred eighty-one thousand, nine hundred eighty-six".