1503561 has 4 divisors (see below), whose sum is σ = 2004752. Its totient is φ = 1002372.

The previous prime is 1503529. The next prime is 1503583. The reversal of 1503561 is 1653051.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1653051 = 3 ⋅551017.

It is not a de Polignac number, because 1503561 - 2⁵ = 1503529 is a prime.

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1503521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 250591 + ... + 250596.

It is an arithmetic number, because the mean of its divisors is an integer number (501188).

2^1503561 is an apocalyptic number.

It is an amenable number.

1503561 is a deficient number, since it is larger than the sum of its proper divisors (501191).

1503561 is an equidigital number, since it uses as much as digits as its factorization.

1503561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 501190.

The product of its (nonzero) digits is 450, while the sum is 21.

The square root of 1503561 is about 1226.1977817628. The cubic root of 1503561 is about 114.5619377205.

The spelling of 1503561 in words is "one million, five hundred three thousand, five hundred sixty-one".