20811318 has 32 divisors (see below), whose sum is σ = 46379520. Its totient is φ = 6171360.

The previous prime is 20811283. The next prime is 20811331. The reversal of 20811318 is 81311802.

It is a super-2 number, since 2×20811318² = 866221913794248, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 253 + ... + 6456.

It is an arithmetic number, because the mean of its divisors is an integer number (1449360).

Almost surely, 2^20811318 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20811318, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23189760).

20811318 is an abundant number, since it is smaller than the sum of its proper divisors (25568202).

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

20811318 is a wasteful number, since it uses less digits than its factorization.

20811318 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6772.

The product of its (nonzero) digits is 384, while the sum is 24.

The square root of 20811318 is about 4561.9423494823. The cubic root of 20811318 is about 275.0636458748.

The spelling of 20811318 in words is "twenty million, eight hundred eleven thousand, three hundred eighteen".