8391919 has 2 divisors, whose sum is σ = 8391920. Its totient is φ = 8391918.

The previous prime is 8391893. The next prime is 8391937. The reversal of 8391919 is 9191938.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 8391919 - 2⁷ = 8391791 is a prime.

It is a super-2 number, since 2×8391919² = 140848609005122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8391949) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4195959 + 4195960.

It is an arithmetic number, because the mean of its divisors is an integer number (4195960).

Almost surely, 2^8391919 is an apocalyptic number.

8391919 is a deficient number, since it is larger than the sum of its proper divisors (1).

8391919 is an equidigital number, since it uses as much as digits as its factorization.

8391919 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17496, while the sum is 40.

The square root of 8391919 is about 2896.8809088397. The cubic root of 8391919 is about 203.2140639485.

It can be divided in two parts, 83919 and 19, that added together give a palindrome (83938).

The spelling of 8391919 in words is "eight million, three hundred ninety-one thousand, nine hundred nineteen".