20804755 has 4 divisors (see below), whose sum is σ = 24965712. Its totient is φ = 16643800.

The previous prime is 20804747. The next prime is 20804783. The reversal of 20804755 is 55740802.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 20804755 - 2³ = 20804747 is a prime.

It is a super-2 number, since 2×20804755² = 865675661220050, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian 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, 2080471 + ... + 2080480.

It is an arithmetic number, because the mean of its divisors is an integer number (6241428).

Almost surely, 2^20804755 is an apocalyptic number.

20804755 is a deficient number, since it is larger than the sum of its proper divisors (4160957).

20804755 is an equidigital number, since it uses as much as digits as its factorization.

20804755 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4160956.

The product of its (nonzero) digits is 11200, while the sum is 31.

The square root of 20804755 is about 4561.2229719671. Note that the first 3 decimals coincide. The cubic root of 20804755 is about 275.0347283965.

The spelling of 20804755 in words is "twenty million, eight hundred four thousand, seven hundred fifty-five".