20790013 has 4 divisors (see below), whose sum is σ = 21506940. Its totient is φ = 20073088.

The previous prime is 20789927. The next prime is 20790017. The reversal of 20790013 is 31009702.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 7518564 + 13271449 = 2742^2 + 3643^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20790013 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20790017) 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, 358420 + ... + 358477.

It is an arithmetic number, because the mean of its divisors is an integer number (5376735).

Almost surely, 2^20790013 is an apocalyptic number.

It is an amenable number.

20790013 is a deficient number, since it is larger than the sum of its proper divisors (716927).

20790013 is an equidigital number, since it uses as much as digits as its factorization.

20790013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 716926.

The product of its (nonzero) digits is 378, while the sum is 22.

The square root of 20790013 is about 4559.6066716330. The cubic root of 20790013 is about 274.9697509428.

Adding to 20790013 its reverse (31009702), we get a palindrome (51799715).

The spelling of 20790013 in words is "twenty million, seven hundred ninety thousand, thirteen".