1561525 has 12 divisors (see below), whose sum is σ = 2213152. Its totient is φ = 1070640.

The previous prime is 1561519. The next prime is 1561529. The reversal of 1561525 is 5251651.

It is not a de Polignac number, because 1561525 - 2⁹ = 1561013 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1561525.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561529) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4287 + ... + 4636.

2^1561525 is an apocalyptic number.

It is an amenable number.

1561525 is a deficient number, since it is larger than the sum of its proper divisors (651627).

1561525 is an equidigital number, since it uses as much as digits as its factorization.

1561525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8940 (or 8935 counting only the distinct ones).

The product of its digits is 1500, while the sum is 25.

The square root of 1561525 is about 1249.6099391410. The cubic root of 1561525 is about 116.0155795563.

It can be divided in two parts, 156 and 1525, that added together give a square (1681 = 41²).

The spelling of 1561525 in words is "one million, five hundred sixty-one thousand, five hundred twenty-five".