1525591 has 4 divisors (see below), whose sum is σ = 1529032. Its totient is φ = 1522152.

The previous prime is 1525571. The next prime is 1525607. The reversal of 1525591 is 1955251.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1525591 - 2¹⁵ = 1492823 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1525501) 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 in 3 ways as a sum of consecutive naturals, for example, 936 + ... + 1981.

It is an arithmetic number, because the mean of its divisors is an integer number (382258).

2^1525591 is an apocalyptic number.

1525591 is a deficient number, since it is larger than the sum of its proper divisors (3441).

1525591 is an equidigital number, since it uses as much as digits as its factorization.

1525591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3440.

The product of its digits is 2250, while the sum is 28.

The square root of 1525591 is about 1235.1481692493. The cubic root of 1525591 is about 115.1187431342.

It can be divided in two parts, 1525 and 591, that added together give a square (2116 = 46²).

The spelling of 1525591 in words is "one million, five hundred twenty-five thousand, five hundred ninety-one".