20533218 has 32 divisors (see below), whose sum is σ = 42768000. Its totient is φ = 6564096.

The previous prime is 20533213. The next prime is 20533223. The reversal of 20533218 is 81233502.

It is an interprime number because it is at equal distance from previous prime (20533213) and next prime (20533223).

It is a super-2 number, since 2×20533218² = 843226082871048, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20533213) 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, 34330 + ... + 34922.

It is an arithmetic number, because the mean of its divisors is an integer number (1336500).

Almost surely, 2^20533218 is an apocalyptic number.

20533218 is an abundant number, since it is smaller than the sum of its proper divisors (22234782).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20533218 is a wasteful number, since it uses less digits than its factorization.

20533218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 826.

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 20533218 is about 4531.3593986794. The cubic root of 20533218 is about 273.8329295672.

The spelling of 20533218 in words is "twenty million, five hundred thirty-three thousand, two hundred eighteen".