1285581 has 16 divisors (see below), whose sum is σ = 1889280. Its totient is φ = 771120.

The previous prime is 1285553. The next prime is 1285607. The reversal of 1285581 is 1855821.

It is not a de Polignac number, because 1285581 - 2⁵ = 1285549 is a prime.

It is a super-3 number, since 3×1285581³ = 6374110535006333823, which contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1285511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5260 + ... + 5498.

It is an arithmetic number, because the mean of its divisors is an integer number (118080).

2^1285581 is an apocalyptic number.

1285581 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1285581 is a deficient number, since it is larger than the sum of its proper divisors (603699).

1285581 is a wasteful number, since it uses less digits than its factorization.

1285581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 416.

The product of its digits is 3200, while the sum is 30.

The square root of 1285581 is about 1133.8346440288. The cubic root of 1285581 is about 108.7342796672.

It can be divided in two parts, 1 and 285581, that added together give a palindrome (285582).

The spelling of 1285581 in words is "one million, two hundred eighty-five thousand, five hundred eighty-one".