11639881 has 4 divisors (see below), whose sum is σ = 12698064. Its totient is φ = 10581700.

The previous prime is 11639869. The next prime is 11639893. The reversal of 11639881 is 18893611.

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.

It is an interprime number because it is at equal distance from previous prime (11639869) and next prime (11639893).

It is a cyclic number.

It is not a de Polignac number, because 11639881 - 2¹⁹ = 11115593 is a prime.

It is a super-2 number, since 2×11639881² = 270973659388322, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 11639881.

It is not an unprimeable number, because it can be changed into a prime (11639851) 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, 529075 + ... + 529096.

It is an arithmetic number, because the mean of its divisors is an integer number (3174516).

Almost surely, 2^11639881 is an apocalyptic number.

11639881 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

11639881 is a deficient number, since it is larger than the sum of its proper divisors (1058183).

11639881 is a wasteful number, since it uses less digits than its factorization.

11639881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1058182.

The product of its digits is 10368, while the sum is 37.

The square root of 11639881 is about 3411.7269820430. The cubic root of 11639881 is about 226.6293640556.

The spelling of 11639881 in words is "eleven million, six hundred thirty-nine thousand, eight hundred eighty-one".