20004993 has 12 divisors (see below), whose sum is σ = 29292900. Its totient is φ = 13153536.

The previous prime is 20004979. The next prime is 20004997. The reversal of 20004993 is 39940002.

It can be written as a sum of positive squares in 2 ways, for example, as 6411024 + 13593969 = 2532^2 + 3687^2 .

It is not a de Polignac number, because 20004993 - 2⁴ = 20004977 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20004997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 14568 + ... + 15881.

It is an arithmetic number, because the mean of its divisors is an integer number (2441075).

Almost surely, 2^20004993 is an apocalyptic number.

It is an amenable number.

20004993 is a deficient number, since it is larger than the sum of its proper divisors (9287907).

20004993 is a wasteful number, since it uses less digits than its factorization.

20004993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30528 (or 30525 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 27.

The square root of 20004993 is about 4472.6941545337. The cubic root of 20004993 is about 271.4643482586.

Adding to 20004993 its reverse (39940002), we get a palindrome (59944995).

The spelling of 20004993 in words is "twenty million, four thousand, nine hundred ninety-three".