11005661 has 8 divisors (see below), whose sum is σ = 11729664. Its totient is φ = 10302160.

The previous prime is 11005649. The next prime is 11005669. The reversal of 11005661 is 16650011.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-11005661 is a prime.

It is a super-2 number, since 2×11005661² = 242249148093842, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11005669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4010 + ... + 6171.

It is an arithmetic number, because the mean of its divisors is an integer number (1466208).

Almost surely, 2^11005661 is an apocalyptic number.

It is an amenable number.

11005661 is a deficient number, since it is larger than the sum of its proper divisors (724003).

11005661 is a wasteful number, since it uses less digits than its factorization.

11005661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10251.

The product of its (nonzero) digits is 180, while the sum is 20.

The square root of 11005661 is about 3317.4781084432. The cubic root of 11005661 is about 222.4361538817.

Adding to 11005661 its reverse (16650011), we get a palindrome (27655672).

The spelling of 11005661 in words is "eleven million, five thousand, six hundred sixty-one".