1915591 has 2 divisors, whose sum is σ = 1915592. Its totient is φ = 1915590.

The previous prime is 1915567. The next prime is 1915609. The reversal of 1915591 is 1955191.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1915591 - 2¹⁵ = 1882823 is a prime.

1915591 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1915531) 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, 957795 + 957796.

It is an arithmetic number, because the mean of its divisors is an integer number (957796).

2^1915591 is an apocalyptic number.

1915591 is a deficient number, since it is larger than the sum of its proper divisors (1).

1915591 is an equidigital number, since it uses as much as digits as its factorization.

1915591 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2025, while the sum is 31.

The square root of 1915591 is about 1384.0487708170. The cubic root of 1915591 is about 124.1940899045.

The spelling of 1915591 in words is "one million, nine hundred fifteen thousand, five hundred ninety-one".