20355613 has 4 divisors (see below), whose sum is σ = 21553020. Its totient is φ = 19158208.

The previous prime is 20355607. The next prime is 20355617. The reversal of 20355613 is 31655302.

It is a happy number.

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 17623204 + 2732409 = 4198^2 + 1653^2 .

It is a cyclic number.

It is not a de Polignac number, because 20355613 - 2¹⁷ = 20224541 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 (20355617) 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 in 3 ways as a sum of consecutive naturals, for example, 598678 + ... + 598711.

It is an arithmetic number, because the mean of its divisors is an integer number (5388255).

Almost surely, 2^20355613 is an apocalyptic number.

It is an amenable number.

20355613 is a deficient number, since it is larger than the sum of its proper divisors (1197407).

20355613 is a wasteful number, since it uses less digits than its factorization.

20355613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1197406.

The product of its (nonzero) digits is 2700, while the sum is 25.

The square root of 20355613 is about 4511.7195169913. The cubic root of 20355613 is about 273.0411232089.

The spelling of 20355613 in words is "twenty million, three hundred fifty-five thousand, six hundred thirteen".