20065999 has 4 divisors (see below), whose sum is σ = 20757960. Its totient is φ = 19374040.

The previous prime is 20065987. The next prime is 20066003. The reversal of 20065999 is 99956002.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99956002 = 2 ⋅49978001.

It is a cyclic number.

It is not a de Polignac number, because 20065999 - 2¹¹ = 20063951 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20065909) 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, 345937 + ... + 345994.

It is an arithmetic number, because the mean of its divisors is an integer number (5189490).

Almost surely, 2^20065999 is an apocalyptic number.

20065999 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

20065999 is a deficient number, since it is larger than the sum of its proper divisors (691961).

20065999 is an equidigital number, since it uses as much as digits as its factorization.

20065999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 691960.

The product of its (nonzero) digits is 43740, while the sum is 40.

The square root of 20065999 is about 4479.5087900349. The cubic root of 20065999 is about 271.7400152395.

The spelling of 20065999 in words is "twenty million, sixty-five thousand, nine hundred ninety-nine".