20211366 has 32 divisors (see below), whose sum is σ = 46725120. Its totient is φ = 5708736.

The previous prime is 20211263. The next prime is 20211377. The reversal of 20211366 is 66311202.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (21).

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, 1035 + ... + 6441.

It is an arithmetic number, because the mean of its divisors is an integer number (1460160).

Almost surely, 2^20211366 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20211366, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23362560).

20211366 is an abundant number, since it is smaller than the sum of its proper divisors (26513754).

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

20211366 is a wasteful number, since it uses less digits than its factorization.

20211366 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5508.

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 20211366 is about 4495.7052839349. The cubic root of 20211366 is about 272.3946387278.

Adding to 20211366 its reverse (66311202), we get a palindrome (86522568).

The spelling of 20211366 in words is "twenty million, two hundred eleven thousand, three hundred sixty-six".