19691969 has 16 divisors (see below), whose sum is σ = 22057920. Its totient is φ = 17429760.

The previous prime is 19691963. The next prime is 19691977. The reversal of 19691969 is 96919691.

It is a cyclic number.

It is not a de Polignac number, because 19691969 - 2⁴ = 19691953 is a prime.

It is a super-2 number, since 2×19691969² = 775547286193922, which contains 22 as substring.

It is a Duffinian 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 15 ways as a sum of consecutive naturals, for example, 109922 + ... + 110100.

It is an arithmetic number, because the mean of its divisors is an integer number (1378620).

Almost surely, 2^19691969 is an apocalyptic number.

It is an amenable number.

19691969 is a deficient number, since it is larger than the sum of its proper divisors (2365951).

19691969 is a wasteful number, since it uses less digits than its factorization.

19691969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 400.

The product of its digits is 236196, while the sum is 50.

The square root of 19691969 is about 4437.5634079977. The cubic root of 19691969 is about 270.0410042891.

The spelling of 19691969 in words is "nineteen million, six hundred ninety-one thousand, nine hundred sixty-nine".