20649413 has 2 divisors, whose sum is σ = 20649414. Its totient is φ = 20649412.

The previous prime is 20649397. The next prime is 20649439. The reversal of 20649413 is 31494602.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17833729 + 2815684 = 4223^2 + 1678^2 .

It is a cyclic number.

It is not a de Polignac number, because 20649413 - 2⁴ = 20649397 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20649493) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10324706 + 10324707.

It is an arithmetic number, because the mean of its divisors is an integer number (10324707).

Almost surely, 2^20649413 is an apocalyptic number.

It is an amenable number.

20649413 is a deficient number, since it is larger than the sum of its proper divisors (1).

20649413 is an equidigital number, since it uses as much as digits as its factorization.

20649413 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 20649413 is about 4544.1625191007. The cubic root of 20649413 is about 274.3484874488.

The spelling of 20649413 in words is "twenty million, six hundred forty-nine thousand, four hundred thirteen".