13881997 has 2 divisors, whose sum is σ = 13881998. Its totient is φ = 13881996.

The previous prime is 13881983. The next prime is 13882009. The reversal of 13881997 is 79918831.

13881997 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13756681 + 125316 = 3709^2 + 354^2 .

It is an emirp because it is prime and its reverse (79918831) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13881997 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13881977) 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 as a sum of consecutive naturals, namely, 6940998 + 6940999.

It is an arithmetic number, because the mean of its divisors is an integer number (6940999).

Almost surely, 2^13881997 is an apocalyptic number.

It is an amenable number.

13881997 is a deficient number, since it is larger than the sum of its proper divisors (1).

13881997 is an equidigital number, since it uses as much as digits as its factorization.

13881997 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108864, while the sum is 46.

The square root of 13881997 is about 3725.8552038425. The cubic root of 13881997 is about 240.3351625112.

It can be divided in two parts, 13881 and 997, that added together give a triangular number (14878 = T₁₇₂).

The spelling of 13881997 in words is "thirteen million, eight hundred eighty-one thousand, nine hundred ninety-seven".