16418881 has 2 divisors, whose sum is σ = 16418882. Its totient is φ = 16418880.

The previous prime is 16418879. The next prime is 16418887. The reversal of 16418881 is 18881461.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10342656 + 6076225 = 3216^2 + 2465^2 .

It is an emirp because it is prime and its reverse (18881461) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16418881 - 2¹ = 16418879 is a prime.

It is a super-2 number, since 2×16418881² = 539159306584322, which contains 22 as substring.

Together with 16418879, it forms a pair of twin primes.

It is a nialpdrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 16418881.

It is not a weakly prime, because it can be changed into another prime (16418887) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8209440 + 8209441.

It is an arithmetic number, because the mean of its divisors is an integer number (8209441).

Almost surely, 2^16418881 is an apocalyptic number.

It is an amenable number.

16418881 is a deficient number, since it is larger than the sum of its proper divisors (1).

16418881 is an equidigital number, since it uses as much as digits as its factorization.

16418881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12288, while the sum is 37.

The square root of 16418881 is about 4052.0218410073. The cubic root of 16418881 is about 254.1642818851.

The spelling of 16418881 in words is "sixteen million, four hundred eighteen thousand, eight hundred eighty-one".