11668821 has 4 divisors (see below), whose sum is σ = 15558432. Its totient is φ = 7779212.

The previous prime is 11668819. The next prime is 11668823. The reversal of 11668821 is 12886611.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12886611 = 3 ⋅4295537.

It is an interprime number because it is at equal distance from previous prime (11668819) and next prime (11668823).

It is a cyclic number.

It is not a de Polignac number, because 11668821 - 2¹ = 11668819 is a prime.

It is a super-2 number, since 2×11668821² = 272322767060082, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11668823) by changing a digit.

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, 1944801 + ... + 1944806.

It is an arithmetic number, because the mean of its divisors is an integer number (3889608).

Almost surely, 2^11668821 is an apocalyptic number.

It is an amenable number.

11668821 is a deficient number, since it is larger than the sum of its proper divisors (3889611).

11668821 is an equidigital number, since it uses as much as digits as its factorization.

11668821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3889610.

The product of its digits is 4608, while the sum is 33.

The square root of 11668821 is about 3415.9656028713. The cubic root of 11668821 is about 226.8170299416.

The spelling of 11668821 in words is "eleven million, six hundred sixty-eight thousand, eight hundred twenty-one".