1525581 has 8 divisors (see below), whose sum is σ = 2260160. Its totient is φ = 1017036.

The previous prime is 1525571. The next prime is 1525607. The reversal of 1525581 is 1855251.

It is not a de Polignac number, because 1525581 - 2¹⁴ = 1509197 is a prime.

It is a super-2 number, since 2×1525581² = 4654794775122, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 56503 = 1525581 / (1 + 5 + 2 + 5 + 5 + 8 + 1).

It is a Duffinian number.

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 polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28225 + ... + 28278.

It is an arithmetic number, because the mean of its divisors is an integer number (282520).

2^1525581 is an apocalyptic number.

It is an amenable number.

1525581 is a deficient number, since it is larger than the sum of its proper divisors (734579).

1525581 is an equidigital number, since it uses as much as digits as its factorization.

1525581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56512 (or 56506 counting only the distinct ones).

The product of its digits is 2000, while the sum is 27.

The square root of 1525581 is about 1235.1441211454. The cubic root of 1525581 is about 115.1184916055.

The spelling of 1525581 in words is "one million, five hundred twenty-five thousand, five hundred eighty-one".