1505561 has 4 divisors (see below), whose sum is σ = 1542324. Its totient is φ = 1468800.

The previous prime is 1505521. The next prime is 1505563. The reversal of 1505561 is 1655051.

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

It can be written as a sum of positive squares in 2 ways, for example, as 19600 + 1485961 = 140^2 + 1219^2 .

It is a cyclic number.

It is not a de Polignac number, because 1505561 - 2¹⁰ = 1504537 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1505563) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18320 + ... + 18401.

It is an arithmetic number, because the mean of its divisors is an integer number (385581).

2^1505561 is an apocalyptic number.

It is an amenable number.

1505561 is a deficient number, since it is larger than the sum of its proper divisors (36763).

1505561 is an equidigital number, since it uses as much as digits as its factorization.

1505561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36762.

The product of its (nonzero) digits is 750, while the sum is 23.

The square root of 1505561 is about 1227.0130398655. The cubic root of 1505561 is about 114.6127110421.

The spelling of 1505561 in words is "one million, five hundred five thousand, five hundred sixty-one".