20800018 has 16 divisors (see below), whose sum is σ = 32736960. Its totient is φ = 9898000.

The previous prime is 20800007. The next prime is 20800019. The reversal of 20800018 is 81000802.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 20799968 and 20800004.

It is not an unprimeable number, because it can be changed into a prime (20800019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1593 + ... + 6643.

It is an arithmetic number, because the mean of its divisors is an integer number (2046060).

Almost surely, 2^20800018 is an apocalyptic number.

20800018 is a deficient number, since it is larger than the sum of its proper divisors (11936942).

20800018 is a wasteful number, since it uses less digits than its factorization.

20800018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5153.

The product of its (nonzero) digits is 128, while the sum is 19.

The square root of 20800018 is about 4560.7036737767. The cubic root of 20800018 is about 275.0138527457.

The spelling of 20800018 in words is "twenty million, eight hundred thousand, eighteen".