1138391 has 2 divisors, whose sum is σ = 1138392. Its totient is φ = 1138390.

The previous prime is 1138369. The next prime is 1138393. The reversal of 1138391 is 1938311.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1138391 is a prime.

It is a Sophie Germain prime.

Together with 1138393, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1138391.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1138393) 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, 569195 + 569196.

It is an arithmetic number, because the mean of its divisors is an integer number (569196).

2^1138391 is an apocalyptic number.

1138391 is a deficient number, since it is larger than the sum of its proper divisors (1).

1138391 is an equidigital number, since it uses as much as digits as its factorization.

1138391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 648, while the sum is 26.

The square root of 1138391 is about 1066.9540758627. The cubic root of 1138391 is about 104.4152224051.

The spelling of 1138391 in words is "one million, one hundred thirty-eight thousand, three hundred ninety-one".