20855805 has 8 divisors (see below), whose sum is σ = 33369312. Its totient is φ = 11123088.

The previous prime is 20855789. The next prime is 20855831. The reversal of 20855805 is 50855802.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20855805 - 2⁴ = 20855789 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 695179 + ... + 695208.

It is an arithmetic number, because the mean of its divisors is an integer number (4171164).

Almost surely, 2^20855805 is an apocalyptic number.

It is an amenable number.

20855805 is a deficient number, since it is larger than the sum of its proper divisors (12513507).

20855805 is a wasteful number, since it uses less digits than its factorization.

20855805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1390395.

The product of its (nonzero) digits is 16000, while the sum is 33.

The square root of 20855805 is about 4566.8156301738. The cubic root of 20855805 is about 275.2595016028.

The spelling of 20855805 in words is "twenty million, eight hundred fifty-five thousand, eight hundred five".