20013999 has 8 divisors (see below), whose sum is σ = 26716800. Its totient is φ = 13326936.

The previous prime is 20013997. The next prime is 20014009. The reversal of 20013999 is 99931002.

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

It is not a de Polignac number, because 20013999 - 2¹ = 20013997 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20013991) 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, 549 + ... + 6350.

It is an arithmetic number, because the mean of its divisors is an integer number (3339600).

Almost surely, 2^20013999 is an apocalyptic number.

20013999 is a deficient number, since it is larger than the sum of its proper divisors (6702801).

20013999 is an equidigital number, since it uses as much as digits as its factorization.

20013999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7869.

The product of its (nonzero) digits is 4374, while the sum is 33.

The square root of 20013999 is about 4473.7008169970. The cubic root of 20013999 is about 271.5050787759.

It can be divided in two parts, 20013 and 999, that added together give a palindrome (21012).

The spelling of 20013999 in words is "twenty million, thirteen thousand, nine hundred ninety-nine".