20199999 has 8 divisors (see below), whose sum is σ = 27089712. Its totient is φ = 13388480.

The previous prime is 20199973. The next prime is 20200013. The reversal of 20199999 is 99999102.

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 20199999 - 2¹⁶ = 20134463 is a prime.

20199999 is a modest number, since divided by 9999 gives 2019 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20199799) 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, 18942 + ... + 19979.

It is an arithmetic number, because the mean of its divisors is an integer number (3386214).

Almost surely, 2^20199999 is an apocalyptic number.

20199999 is a deficient number, since it is larger than the sum of its proper divisors (6889713).

20199999 is a wasteful number, since it uses less digits than its factorization.

20199999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39097.

The product of its (nonzero) digits is 118098, while the sum is 48.

The square root of 20199999 is about 4494.4408996003. The cubic root of 20199999 is about 272.3435636628.

The spelling of 20199999 in words is "twenty million, one hundred ninety-nine thousand, nine hundred ninety-nine".