1287261 has 12 divisors (see below), whose sum is σ = 1869660. Its totient is φ = 853440.

The previous prime is 1287239. The next prime is 1287289. The reversal of 1287261 is 1627821.

It can be written as a sum of positive squares in 2 ways, for example, as 962361 + 324900 = 981^2 + 570^2 .

It is not a de Polignac number, because 1287261 - 2⁶ = 1287197 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1287061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2275 + ... + 2783.

It is an arithmetic number, because the mean of its divisors is an integer number (155805).

2^1287261 is an apocalyptic number.

It is an amenable number.

1287261 is a deficient number, since it is larger than the sum of its proper divisors (582399).

1287261 is a wasteful number, since it uses less digits than its factorization.

1287261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 796 (or 793 counting only the distinct ones).

The product of its digits is 1344, while the sum is 27.

The square root of 1287261 is about 1134.5752509199. The cubic root of 1287261 is about 108.7816237797.

The spelling of 1287261 in words is "one million, two hundred eighty-seven thousand, two hundred sixty-one".