19999799 has 8 divisors (see below), whose sum is σ = 21194880. Its totient is φ = 18819000.

The previous prime is 19999789. The next prime is 19999817. The reversal of 19999799 is 99799991.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 19999799 - 2⁸ = 19999543 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19999729) 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, 617 + ... + 6354.

It is an arithmetic number, because the mean of its divisors is an integer number (2649360).

Almost surely, 2^19999799 is an apocalyptic number.

19999799 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

19999799 is a deficient number, since it is larger than the sum of its proper divisors (1195081).

19999799 is a wasteful number, since it uses less digits than its factorization.

19999799 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7141.

The product of its digits is 3720087, while the sum is 62.

The square root of 19999799 is about 4472.1134824599. The cubic root of 19999799 is about 271.4408523265.

The spelling of 19999799 in words is "nineteen million, nine hundred ninety-nine thousand, seven hundred ninety-nine".