19691097 has 16 divisors (see below), whose sum is σ = 26756352. Its totient is φ = 12879360.

The previous prime is 19691053. The next prime is 19691129. The reversal of 19691097 is 79019691.

It is not a de Polignac number, because 19691097 - 2⁸ = 19690841 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19691017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 45472 + ... + 45902.

It is an arithmetic number, because the mean of its divisors is an integer number (1672272).

Almost surely, 2^19691097 is an apocalyptic number.

It is an amenable number.

19691097 is a deficient number, since it is larger than the sum of its proper divisors (7065255).

19691097 is a wasteful number, since it uses less digits than its factorization.

19691097 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 688.

The product of its (nonzero) digits is 30618, while the sum is 42.

The square root of 19691097 is about 4437.4651547928. The cubic root of 19691097 is about 270.0370182440.

The spelling of 19691097 in words is "nineteen million, six hundred ninety-one thousand, ninety-seven".