1285181 has 2 divisors, whose sum is σ = 1285182. Its totient is φ = 1285180.

The previous prime is 1285169. The next prime is 1285199. The reversal of 1285181 is 1815821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1276900 + 8281 = 1130^2 + 91^2 .

It is a cyclic number.

It is not a de Polignac number, because 1285181 - 2⁶ = 1285117 is a prime.

It is a super-2 number, since 2×1285181² = 3303380405522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1285181.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1285111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 642590 + 642591.

It is an arithmetic number, because the mean of its divisors is an integer number (642591).

2^1285181 is an apocalyptic number.

It is an amenable number.

1285181 is a deficient number, since it is larger than the sum of its proper divisors (1).

1285181 is an equidigital number, since it uses as much as digits as its factorization.

1285181 is an evil number, because the sum of its binary digits is even.

The product of its digits is 640, while the sum is 26.

The square root of 1285181 is about 1133.6582377419. The cubic root of 1285181 is about 108.7230011807.

Adding to 1285181 its product of digits (640), we get a palindrome (1285821).

The spelling of 1285181 in words is "one million, two hundred eighty-five thousand, one hundred eighty-one".