20115993 has 16 divisors (see below), whose sum is σ = 27877376. Its totient is φ = 12888720.

The previous prime is 20115989. The next prime is 20116001. The reversal of 20115993 is 39951102.

It is not a de Polignac number, because 20115993 - 2² = 20115989 is a prime.

It is a Smith number, since the sum of its digits (30) 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 self number, because there is not a number n which added to its sum of digits gives 20115993.

It is not an unprimeable number, because it can be changed into a prime (20115983) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14496 + ... + 15822.

It is an arithmetic number, because the mean of its divisors is an integer number (1742336).

Almost surely, 2^20115993 is an apocalyptic number.

It is an amenable number.

20115993 is a deficient number, since it is larger than the sum of its proper divisors (7761383).

20115993 is a wasteful number, since it uses less digits than its factorization.

20115993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1524.

The product of its (nonzero) digits is 2430, while the sum is 30.

The square root of 20115993 is about 4485.0856179119. The cubic root of 20115993 is about 271.9655061867.

The spelling of 20115993 in words is "twenty million, one hundred fifteen thousand, nine hundred ninety-three".