19904693 has 4 divisors (see below), whose sum is σ = 19935468. Its totient is φ = 19873920.

The previous prime is 19904681. The next prime is 19904707. The reversal of 19904693 is 39640991.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 17322244 + 2582449 = 4162^2 + 1607^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19904693 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 19904693.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19904663) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14396 + ... + 15717.

It is an arithmetic number, because the mean of its divisors is an integer number (4983867).

Almost surely, 2^19904693 is an apocalyptic number.

It is an amenable number.

19904693 is a deficient number, since it is larger than the sum of its proper divisors (30775).

19904693 is an equidigital number, since it uses as much as digits as its factorization.

19904693 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30774.

The product of its (nonzero) digits is 52488, while the sum is 41.

The square root of 19904693 is about 4461.4675836545. The cubic root of 19904693 is about 271.0099032796.

The spelling of 19904693 in words is "nineteen million, nine hundred four thousand, six hundred ninety-three".