20550605 has 4 divisors (see below), whose sum is σ = 24660732. Its totient is φ = 16440480.

The previous prime is 20550599. The next prime is 20550617. The reversal of 20550605 is 50605502.

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 10329796 + 10220809 = 3214^2 + 3197^2 .

It is a de Polignac number, because none of the positive numbers 2^k-20550605 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2055056 + ... + 2055065.

It is an arithmetic number, because the mean of its divisors is an integer number (6165183).

Almost surely, 2^20550605 is an apocalyptic number.

It is an amenable number.

20550605 is a deficient number, since it is larger than the sum of its proper divisors (4110127).

20550605 is an equidigital number, since it uses as much as digits as its factorization.

20550605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4110126.

The product of its (nonzero) digits is 1500, while the sum is 23.

The square root of 20550605 is about 4533.2775119112. The cubic root of 20550605 is about 273.9101993179.

The spelling of 20550605 in words is "twenty million, five hundred fifty thousand, six hundred five".