20641013 has 2 divisors, whose sum is σ = 20641014. Its totient is φ = 20641012.

The previous prime is 20641007. The next prime is 20641039. The reversal of 20641013 is 31014602.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20584369 + 56644 = 4537^2 + 238^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20641013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20640982 and 20641000.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20641063) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10320506 + 10320507.

It is an arithmetic number, because the mean of its divisors is an integer number (10320507).

Almost surely, 2^20641013 is an apocalyptic number.

It is an amenable number.

20641013 is a deficient number, since it is larger than the sum of its proper divisors (1).

20641013 is an equidigital number, since it uses as much as digits as its factorization.

20641013 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 20641013 is about 4543.2381623683. The cubic root of 20641013 is about 274.3112815510.

Adding to 20641013 its reverse (31014602), we get a palindrome (51655615).

The spelling of 20641013 in words is "twenty million, six hundred forty-one thousand, thirteen".