20634613 has 2 divisors, whose sum is σ = 20634614. Its totient is φ = 20634612.

The previous prime is 20634571. The next prime is 20634619. The reversal of 20634613 is 31643602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20277009 + 357604 = 4503^2 + 598^2 .

It is a cyclic number.

It is not a de Polignac number, because 20634613 - 2⁹ = 20634101 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20634619) 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 as a sum of consecutive naturals, namely, 10317306 + 10317307.

It is an arithmetic number, because the mean of its divisors is an integer number (10317307).

Almost surely, 2^20634613 is an apocalyptic number.

It is an amenable number.

20634613 is a deficient number, since it is larger than the sum of its proper divisors (1).

20634613 is an equidigital number, since it uses as much as digits as its factorization.

20634613 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592, while the sum is 25.

The square root of 20634613 is about 4542.5337643214. The cubic root of 20634613 is about 274.2829274245.

The spelling of 20634613 in words is "twenty million, six hundred thirty-four thousand, six hundred thirteen".