11939881 has 2 divisors, whose sum is σ = 11939882. Its totient is φ = 11939880.

The previous prime is 11939849. The next prime is 11939887. The reversal of 11939881 is 18893911.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10208025 + 1731856 = 3195^2 + 1316^2 .

It is a cyclic number.

It is not a de Polignac number, because 11939881 - 2⁵ = 11939849 is a prime.

It is a super-2 number, since 2×11939881² = 285121516588322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (11939887) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5969940 + 5969941.

It is an arithmetic number, because the mean of its divisors is an integer number (5969941).

Almost surely, 2^11939881 is an apocalyptic number.

It is an amenable number.

11939881 is a deficient number, since it is larger than the sum of its proper divisors (1).

11939881 is an equidigital number, since it uses as much as digits as its factorization.

11939881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15552, while the sum is 40.

The square root of 11939881 is about 3455.4132893187. The cubic root of 11939881 is about 228.5598800527.

It can be divided in two parts, 119 and 39881, that added together give a square (40000 = 200²).

The spelling of 11939881 in words is "eleven million, nine hundred thirty-nine thousand, eight hundred eighty-one".