11661020 has 72 divisors (see below), whose sum is σ = 29053584. Its totient is φ = 3919104.

The previous prime is 11661019. The next prime is 11661037. The reversal of 11661020 is 2016611.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 11661020.

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, 71459 + ... + 71621.

It is an arithmetic number, because the mean of its divisors is an integer number (403522).

Almost surely, 2^11661020 is an apocalyptic number.

11661020 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 11661020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14526792).

11661020 is an abundant number, since it is smaller than the sum of its proper divisors (17392564).

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

11661020 is a wasteful number, since it uses less digits than its factorization.

11661020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 259 (or 250 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 17.

The square root of 11661020 is about 3414.8235679168. The cubic root of 11661020 is about 226.7664737315.

Adding to 11661020 its reverse (2016611), we get a palindrome (13677631).

The spelling of 11661020 in words is "eleven million, six hundred sixty-one thousand, twenty".