11641681 has 2 divisors, whose sum is σ = 11641682. Its totient is φ = 11641680.

The previous prime is 11641639. The next prime is 11641687. The reversal of 11641681 is 18614611.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6713281 + 4928400 = 2591^2 + 2220^2 .

It is an emirp because it is prime and its reverse (18614611) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 11641681 - 2¹⁵ = 11608913 is a prime.

It is a super-3 number, since 3×11641681³ (a number of 22 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (11641687) 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 as a sum of consecutive naturals, namely, 5820840 + 5820841.

It is an arithmetic number, because the mean of its divisors is an integer number (5820841).

Almost surely, 2^11641681 is an apocalyptic number.

It is an amenable number.

11641681 is a deficient number, since it is larger than the sum of its proper divisors (1).

11641681 is an equidigital number, since it uses as much as digits as its factorization.

11641681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1152, while the sum is 28.

The square root of 11641681 is about 3411.9907678656. The cubic root of 11641681 is about 226.6410454989.

The spelling of 11641681 in words is "eleven million, six hundred forty-one thousand, six hundred eighty-one".