11871989 has 2 divisors, whose sum is σ = 11871990. Its totient is φ = 11871988.

The previous prime is 11871983. The next prime is 11872013. The reversal of 11871989 is 98917811.

11871989 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11662225 + 209764 = 3415^2 + 458^2 .

It is a cyclic number.

It is not a de Polignac number, because 11871989 - 2⁴ = 11871973 is a prime.

It is a super-2 number, since 2×11871989² = 281888245632242, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11871983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5935994 + 5935995.

It is an arithmetic number, because the mean of its divisors is an integer number (5935995).

Almost surely, 2^11871989 is an apocalyptic number.

It is an amenable number.

11871989 is a deficient number, since it is larger than the sum of its proper divisors (1).

11871989 is an equidigital number, since it uses as much as digits as its factorization.

11871989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36288, while the sum is 44.

The square root of 11871989 is about 3445.5752785275. The cubic root of 11871989 is about 228.1258474729.

The spelling of 11871989 in words is "eleven million, eight hundred seventy-one thousand, nine hundred eighty-nine".