11681851 has 4 divisors (see below), whose sum is σ = 11689272. Its totient is φ = 11674432.

The previous prime is 11681837. The next prime is 11681869. The reversal of 11681851 is 15818611.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 15818611 = 563 ⋅28097.

It is a cyclic number.

It is not a de Polignac number, because 11681851 - 2¹⁵ = 11649083 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11681801) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 310 + ... + 4843.

It is an arithmetic number, because the mean of its divisors is an integer number (2922318).

Almost surely, 2^11681851 is an apocalyptic number.

11681851 is a deficient number, since it is larger than the sum of its proper divisors (7421).

11681851 is an equidigital number, since it uses as much as digits as its factorization.

11681851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7420.

The product of its digits is 1920, while the sum is 31.

The square root of 11681851 is about 3417.8722913532. The cubic root of 11681851 is about 226.9014236869.

The spelling of 11681851 in words is "eleven million, six hundred eighty-one thousand, eight hundred fifty-one".