20193999 has 8 divisors (see below), whose sum is σ = 30771840. Its totient is φ = 11539416.

The previous prime is 20193991. The next prime is 20194037. The reversal of 20193999 is 99939102.

It is a happy number.

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

It is not a de Polignac number, because 20193999 - 2³ = 20193991 is a prime.

It is a super-2 number, since 2×20193999² = 815595191224002, which contains 22 as substring.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 20193999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20193991) 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, 480789 + ... + 480830.

It is an arithmetic number, because the mean of its divisors is an integer number (3846480).

Almost surely, 2^20193999 is an apocalyptic number.

20193999 is a deficient number, since it is larger than the sum of its proper divisors (10577841).

20193999 is an equidigital number, since it uses as much as digits as its factorization.

20193999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 961629.

The product of its (nonzero) digits is 39366, while the sum is 42.

The square root of 20193999 is about 4493.7733587710. The cubic root of 20193999 is about 272.3165962819.

The spelling of 20193999 in words is "twenty million, one hundred ninety-three thousand, nine hundred ninety-nine".