11666678389 has 4 divisors (see below), whose sum is σ = 11685587724. Its totient is φ = 11647769056.

The previous prime is 11666678377. The next prime is 11666678411. The reversal of 11666678389 is 98387666611.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6062958225 + 5603720164 = 77865^2 + 74858^2 .

It is a cyclic number.

It is not a de Polignac number, because 11666678389 - 2¹¹ = 11666676341 is a prime.

It is a super-3 number, since 3×11666678389³ (a number of 31 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11666678189) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9453742 + ... + 9454975.

It is an arithmetic number, because the mean of its divisors is an integer number (2921396931).

Almost surely, 2^11666678389 is an apocalyptic number.

It is an amenable number.

11666678389 is a deficient number, since it is larger than the sum of its proper divisors (18909335).

11666678389 is an equidigital number, since it uses as much as digits as its factorization.

11666678389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18909334.

The product of its digits is 15676416, while the sum is 61.

It can be divided in two parts, 1166667 and 8389, that added together give a square (1175056 = 1084²).

The spelling of 11666678389 in words is "eleven billion, six hundred sixty-six million, six hundred seventy-eight thousand, three hundred eighty-nine".