11661111 has 64 divisors (see below), whose sum is σ = 22118400. Its totient is φ = 5896800.

The previous prime is 11661101. The next prime is 11661119. The reversal of 11661111 is 11116611.

11661111 is a `hidden beast` number, since 1 + 1 + 661 + 1 + 1 + 1 = 666.

It is not a de Polignac number, because 11661111 - 2⁷ = 11660983 is a prime.

It is a zygodrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11661119) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 147570 + ... + 147648.

It is an arithmetic number, because the mean of its divisors is an integer number (345600).

Almost surely, 2^11661111 is an apocalyptic number.

11661111 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

11661111 is a deficient number, since it is larger than the sum of its proper divisors (10457289).

11661111 is a wasteful number, since it uses less digits than its factorization.

11661111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 177 (or 171 counting only the distinct ones).

The product of its digits is 36, while the sum is 18.

The square root of 11661111 is about 3414.8368921517. The cubic root of 11661111 is about 226.7670636083.

Adding to 11661111 its reverse (11116611), we get a palindrome (22777722).

The spelling of 11661111 in words is "eleven million, six hundred sixty-one thousand, one hundred eleven".