1285581025 has 27 divisors (see below), whose sum is σ = 1633056409. Its totient is φ = 1003940000.

The previous prime is 1285581023. The next prime is 1285581029. The reversal of 1285581025 is 5201855821.

The square root of 1285581025 is 35855.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 237375649 + 1048205376 = 15407^2 + 32376^2 .

It is not a de Polignac number, because 1285581025 - 2¹ = 1285581023 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1285581023) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 12728475 + ... + 12728575.

Almost surely, 2^1285581025 is an apocalyptic number.

1285581025 is the 35855-th square number.

1285581025 is the 17928-th centered octagonal number.

It is an amenable number.

1285581025 is a deficient number, since it is larger than the sum of its proper divisors (347475384).

1285581025 is an frugal number, since it uses more digits than its factorization.

1285581025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 354 (or 177 counting only the distinct ones).

The product of its (nonzero) digits is 32000, while the sum is 37.

The cubic root of 1285581025 is about 1087.3428037198.

The spelling of 1285581025 in words is "one billion, two hundred eighty-five million, five hundred eighty-one thousand, twenty-five".