20355218 has 16 divisors (see below), whose sum is σ = 32961600. Its totient is φ = 9371856.

The previous prime is 20355193. The next prime is 20355221. The reversal of 20355218 is 81255302.

It is a Harshad number since it is a multiple of its sum of digits (26).

It is an unprimeable number.

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, 14921 + ... + 16227.

It is an arithmetic number, because the mean of its divisors is an integer number (2060100).

Almost surely, 2^20355218 is an apocalyptic number.

20355218 is a deficient number, since it is larger than the sum of its proper divisors (12606382).

20355218 is a wasteful number, since it uses less digits than its factorization.

20355218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1921.

The product of its (nonzero) digits is 2400, while the sum is 26.

The square root of 20355218 is about 4511.6757418946. The cubic root of 20355218 is about 273.0393570795.

The spelling of 20355218 in words is "twenty million, three hundred fifty-five thousand, two hundred eighteen".