20904085 has 16 divisors (see below), whose sum is σ = 26530560. Its totient is φ = 15768000.

The previous prime is 20904077. The next prime is 20904089. The reversal of 20904085 is 58040902.

It is a happy number.

It is not a de Polignac number, because 20904085 - 2³ = 20904077 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20904089) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27460 + ... + 28210.

It is an arithmetic number, because the mean of its divisors is an integer number (1658160).

Almost surely, 2^20904085 is an apocalyptic number.

It is an amenable number.

20904085 is a deficient number, since it is larger than the sum of its proper divisors (5626475).

20904085 is a wasteful number, since it uses less digits than its factorization.

20904085 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1068.

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 20904085 is about 4572.0985334964. The cubic root of 20904085 is about 275.4717412657.

Adding to 20904085 its reverse (58040902), we get a palindrome (78944987).

The spelling of 20904085 in words is "twenty million, nine hundred four thousand, eighty-five".