19691966 has 16 divisors (see below), whose sum is σ = 34477056. Its totient is φ = 8259576.

The previous prime is 19691963. The next prime is 19691977. The reversal of 19691966 is 66919691.

It is a Harshad number since it is a multiple of its sum of digits (47).

It is a self number, because there is not a number n which added to its sum of digits gives 19691966.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19691963) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14306 + ... + 15621.

It is an arithmetic number, because the mean of its divisors is an integer number (2154816).

Almost surely, 2^19691966 is an apocalyptic number.

19691966 is a deficient number, since it is larger than the sum of its proper divisors (14785090).

19691966 is a wasteful number, since it uses less digits than its factorization.

19691966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29983.

The product of its digits is 157464, while the sum is 47.

The square root of 19691966 is about 4437.5630699743. The cubic root of 19691966 is about 270.0409905759.

The spelling of 19691966 in words is "nineteen million, six hundred ninety-one thousand, nine hundred sixty-six".