20183993 has 4 divisors (see below), whose sum is σ = 20194020. Its totient is φ = 20173968.

The previous prime is 20183957. The next prime is 20184011. The reversal of 20183993 is 39938102.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 13017664 + 7166329 = 3608^2 + 2677^2 .

It is a cyclic number.

It is not a de Polignac number, because 20183993 - 2⁶ = 20183929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20183393) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 830 + ... + 6407.

It is an arithmetic number, because the mean of its divisors is an integer number (5048505).

Almost surely, 2^20183993 is an apocalyptic number.

It is an amenable number.

20183993 is a deficient number, since it is larger than the sum of its proper divisors (10027).

20183993 is an equidigital number, since it uses as much as digits as its factorization.

20183993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10026.

The product of its (nonzero) digits is 11664, while the sum is 35.

The square root of 20183993 is about 4492.6599025522. The cubic root of 20183993 is about 272.2716117954.

The spelling of 20183993 in words is "twenty million, one hundred eighty-three thousand, nine hundred ninety-three".