20605013 has 16 divisors (see below), whose sum is σ = 24494400. Its totient is φ = 17086080.

The previous prime is 20604973. The next prime is 20605019. The reversal of 20605013 is 31050602.

It is a de Polignac number, because none of the positive numbers 2^k-20605013 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20604982 and 20605000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20605019) 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, 11918 + ... + 13536.

It is an arithmetic number, because the mean of its divisors is an integer number (1530900).

Almost surely, 2^20605013 is an apocalyptic number.

It is an amenable number.

20605013 is a deficient number, since it is larger than the sum of its proper divisors (3889387).

20605013 is a wasteful number, since it uses less digits than its factorization.

20605013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1732.

The product of its (nonzero) digits is 180, while the sum is 17.

The square root of 20605013 is about 4539.2745015035. The cubic root of 20605013 is about 274.1517132710.

Adding to 20605013 its reverse (31050602), we get a palindrome (51655615).

The spelling of 20605013 in words is "twenty million, six hundred five thousand, thirteen".