16678391 has 2 divisors, whose sum is σ = 16678392. Its totient is φ = 16678390.

The previous prime is 16678357. The next prime is 16678399. The reversal of 16678391 is 19387661.

It is a strong prime.

It is an emirp because it is prime and its reverse (19387661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16678391 - 2¹⁴ = 16662007 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16678399) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8339195 + 8339196.

It is an arithmetic number, because the mean of its divisors is an integer number (8339196).

Almost surely, 2^16678391 is an apocalyptic number.

16678391 is a deficient number, since it is larger than the sum of its proper divisors (1).

16678391 is an equidigital number, since it uses as much as digits as its factorization.

16678391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 54432, while the sum is 41.

The square root of 16678391 is about 4083.9185839093. The cubic root of 16678391 is about 255.4963598732.

The spelling of 16678391 in words is "sixteen million, six hundred seventy-eight thousand, three hundred ninety-one".