11661388 has 12 divisors (see below), whose sum is σ = 21607992. Its totient is φ = 5487680.

The previous prime is 11661379. The next prime is 11661407. The reversal of 11661388 is 88316611.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 85678 + ... + 85813.

It is an arithmetic number, because the mean of its divisors is an integer number (1800666).

Almost surely, 2^11661388 is an apocalyptic number.

It is an amenable number.

11661388 is a deficient number, since it is larger than the sum of its proper divisors (9946604).

11661388 is a wasteful number, since it uses less digits than its factorization.

11661388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171512 (or 171510 counting only the distinct ones).

The product of its digits is 6912, while the sum is 34.

The square root of 11661388 is about 3414.8774502169. The cubic root of 11661388 is about 226.7688591484.

Adding to 11661388 its reverse (88316611), we get a palindrome (99977999).

It can be divided in two parts, 116 and 61388, that added together give a square (61504 = 248²).

The spelling of 11661388 in words is "eleven million, six hundred sixty-one thousand, three hundred eighty-eight".