20604785 has 4 divisors (see below), whose sum is σ = 24725748. Its totient is φ = 16483824.

The previous prime is 20604781. The next prime is 20604809. The reversal of 20604785 is 58740602.

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 12759184 + 7845601 = 3572^2 + 2801^2 .

It is a cyclic number.

It is not a de Polignac number, because 20604785 - 2² = 20604781 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20604781) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2060474 + ... + 2060483.

It is an arithmetic number, because the mean of its divisors is an integer number (6181437).

Almost surely, 2^20604785 is an apocalyptic number.

It is an amenable number.

20604785 is a deficient number, since it is larger than the sum of its proper divisors (4120963).

20604785 is an equidigital number, since it uses as much as digits as its factorization.

20604785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4120962.

The product of its (nonzero) digits is 13440, while the sum is 32.

The square root of 20604785 is about 4539.2493872886. The cubic root of 20604785 is about 274.1507020798.

The spelling of 20604785 in words is "twenty million, six hundred four thousand, seven hundred eighty-five".