11661000 has 192 divisors, whose sum is σ = 41109120. Its totient is φ = 2745600.

The previous prime is 11660993. The next prime is 11661011. The reversal of 11661000 is 16611.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 506989 + ... + 507011.

It is an arithmetic number, because the mean of its divisors is an integer number (214110).

Almost surely, 2^11661000 is an apocalyptic number.

11661000 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 11661000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20554560).

11661000 is an abundant number, since it is smaller than the sum of its proper divisors (29448120).

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

11661000 is a wasteful number, since it uses less digits than its factorization.

11661000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73 (or 46 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 15.

The square root of 11661000 is about 3414.8206395066. The cubic root of 11661000 is about 226.7663440878.

Adding to 11661000 its reverse (16611), we get a palindrome (11677611).

It can be divided in two parts, 116 and 61000, that added together give a palindrome (61116).

The spelling of 11661000 in words is "eleven million, six hundred sixty-one thousand".