13837981 has 2 divisors, whose sum is σ = 13837982. Its totient is φ = 13837980.

The previous prime is 13837969. The next prime is 13838021. The reversal of 13837981 is 18973831.

It is an a-pointer prime, because the next prime (13838021) can be obtained adding 13837981 to its sum of digits (40).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13205956 + 632025 = 3634^2 + 795^2 .

It is an emirp because it is prime and its reverse (18973831) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13837981 - 2⁹ = 13837469 is a prime.

It is a super-2 number, since 2×13837981² = 382979436312722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13837921) 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, 6918990 + 6918991.

It is an arithmetic number, because the mean of its divisors is an integer number (6918991).

Almost surely, 2^13837981 is an apocalyptic number.

It is an amenable number.

13837981 is a deficient number, since it is larger than the sum of its proper divisors (1).

13837981 is an equidigital number, since it uses as much as digits as its factorization.

13837981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36288, while the sum is 40.

The square root of 13837981 is about 3719.9436823694. The cubic root of 13837981 is about 240.0808813043.

The spelling of 13837981 in words is "thirteen million, eight hundred thirty-seven thousand, nine hundred eighty-one".