16422781 has 2 divisors, whose sum is σ = 16422782. Its totient is φ = 16422780.

The previous prime is 16422767. The next prime is 16422793. The reversal of 16422781 is 18722461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15920100 + 502681 = 3990^2 + 709^2 .

It is an emirp because it is prime and its reverse (18722461) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16422781 - 2⁹ = 16422269 is a prime.

It is a super-2 number, since 2×16422781² = 539415471547922, which contains 22 as substring.

It is a zygodrome in base 12.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16422761) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8211390 + 8211391.

It is an arithmetic number, because the mean of its divisors is an integer number (8211391).

Almost surely, 2^16422781 is an apocalyptic number.

It is an amenable number.

16422781 is a deficient number, since it is larger than the sum of its proper divisors (1).

16422781 is an equidigital number, since it uses as much as digits as its factorization.

16422781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5376, while the sum is 31.

The square root of 16422781 is about 4052.5030536694. The cubic root of 16422781 is about 254.1844042923.

The spelling of 16422781 in words is "sixteen million, four hundred twenty-two thousand, seven hundred eighty-one".