19913966 has 8 divisors (see below), whose sum is σ = 30834624. Its totient is φ = 9635760.

The previous prime is 19913963. The next prime is 19913977. The reversal of 19913966 is 66931991.

It is a happy number.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19913963) 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 3 ways as a sum of consecutive naturals, for example, 160535 + ... + 160658.

It is an arithmetic number, because the mean of its divisors is an integer number (3854328).

Almost surely, 2^19913966 is an apocalyptic number.

19913966 is a deficient number, since it is larger than the sum of its proper divisors (10920658).

19913966 is a wasteful number, since it uses less digits than its factorization.

19913966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 321226.

The product of its digits is 78732, while the sum is 44.

The square root of 19913966 is about 4462.5066946728. The cubic root of 19913966 is about 271.0519818768.

The spelling of 19913966 in words is "nineteen million, nine hundred thirteen thousand, nine hundred sixty-six".