11636820 has 72 divisors (see below), whose sum is σ = 38021256. Its totient is φ = 2863872.

The previous prime is 11636813. The next prime is 11636831. The reversal of 11636820 is 2863611.

11636820 is a `hidden beast` number, since 1 + 1 + 636 + 8 + 20 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 467856 + 11168964 = 684^2 + 3342^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 147 + ... + 4826.

It is an arithmetic number, because the mean of its divisors is an integer number (528073).

Almost surely, 2^11636820 is an apocalyptic number.

11636820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 11636820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19010628).

11636820 is an abundant number, since it is smaller than the sum of its proper divisors (26384436).

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

11636820 is a wasteful number, since it uses less digits than its factorization.

11636820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5001 (or 4996 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 11636820 is about 3411.2783527587. The cubic root of 11636820 is about 226.6094963467.

The spelling of 11636820 in words is "eleven million, six hundred thirty-six thousand, eight hundred twenty".