1555091 has 2 divisors, whose sum is σ = 1555092. Its totient is φ = 1555090.

The previous prime is 1555079. The next prime is 1555111. The reversal of 1555091 is 1905551.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1555091 - 2⁶ = 1555027 is a prime.

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 1555091.

It is not a weakly prime, because it can be changed into another prime (1555051) 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, 777545 + 777546.

It is an arithmetic number, because the mean of its divisors is an integer number (777546).

2^1555091 is an apocalyptic number.

1555091 is a deficient number, since it is larger than the sum of its proper divisors (1).

1555091 is an equidigital number, since it uses as much as digits as its factorization.

1555091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1125, while the sum is 26.

The square root of 1555091 is about 1247.0328784759. The cubic root of 1555091 is about 115.8560193419.

The spelling of 1555091 in words is "one million, five hundred fifty-five thousand, ninety-one".