11949681 has 4 divisors (see below), whose sum is σ = 15932912. Its totient is φ = 7966452.

The previous prime is 11949671. The next prime is 11949701. The reversal of 11949681 is 18694911.

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: 18694911 = 3 ⋅6231637.

It is not a de Polignac number, because 11949681 - 2⁵ = 11949649 is a prime.

It is a super-2 number, since 2×11949681² = 285589752003522, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (11949611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1991611 + ... + 1991616.

It is an arithmetic number, because the mean of its divisors is an integer number (3983228).

Almost surely, 2^11949681 is an apocalyptic number.

It is an amenable number.

11949681 is a deficient number, since it is larger than the sum of its proper divisors (3983231).

11949681 is an equidigital number, since it uses as much as digits as its factorization.

11949681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3983230.

The product of its digits is 15552, while the sum is 39.

The square root of 11949681 is about 3456.8310632717. The cubic root of 11949681 is about 228.6223953124.

The spelling of 11949681 in words is "eleven million, nine hundred forty-nine thousand, six hundred eighty-one".