1591555 has 16 divisors (see below), whose sum is σ = 2243520. Its totient is φ = 1060992.

The previous prime is 1591553. The next prime is 1591567. The reversal of 1591555 is 5551951.

It is a cyclic number.

It is not a de Polignac number, because 1591555 - 2¹ = 1591553 is a prime.

1591555 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1591553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 681 + ... + 1909.

It is an arithmetic number, because the mean of its divisors is an integer number (140220).

2^1591555 is an apocalyptic number.

1591555 is a deficient number, since it is larger than the sum of its proper divisors (651965).

1591555 is a wasteful number, since it uses less digits than its factorization.

1591555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1278.

The product of its digits is 5625, while the sum is 31.

The square root of 1591555 is about 1261.5684682172. The cubic root of 1591555 is about 116.7545686746.

The spelling of 1591555 in words is "one million, five hundred ninety-one thousand, five hundred fifty-five".