15391 has 2 divisors, whose sum is σ = 15392.
Its totient is φ = 15390.
The previous prime is 15383. The next prime is 15401. The reversal of 15391 is 19351.
It is a weak prime.
It is a cyclic number.
It is not a de Polignac number, because 15391 - 23 = 15383 is a prime.
It is a zygodrome in base 2.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (15331) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7695 + 7696.
It is an arithmetic number, because the mean of its divisors is an integer number (7696).
215391 is an apocalyptic number.
15391 is a deficient number, since it is larger than the sum of its proper divisors (1).
15391 is an equidigital number, since it uses as much as digits as its factorization.
15391 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 135, while the sum is 19.
The square root of 15391 is about 124.0604691270.
The cubic root of 15391 is about 24.8745717627.
It can be divided in two parts, 1539 and 1, that added together give a triangular number (1540 = T55).
The spelling of 15391 in words is "fifteen thousand, three hundred ninety-one".