19999393 has 4 divisors (see below), whose sum is σ = 20424960. Its totient is φ = 19573828.

The previous prime is 19999387. The next prime is 19999411. The reversal of 19999393 is 39399991.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19999393 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 19999393.

It is not an unprimeable number, because it can be changed into a prime (19999303) 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, 212713 + ... + 212806.

It is an arithmetic number, because the mean of its divisors is an integer number (5106240).

Almost surely, 2^19999393 is an apocalyptic number.

It is an amenable number.

19999393 is a deficient number, since it is larger than the sum of its proper divisors (425567).

19999393 is an equidigital number, since it uses as much as digits as its factorization.

19999393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 425566.

The product of its digits is 531441, while the sum is 52.

The square root of 19999393 is about 4472.0680898215. The cubic root of 19999393 is about 271.4390155459.

The spelling of 19999393 in words is "nineteen million, nine hundred ninety-nine thousand, three hundred ninety-three".