1265681 has 2 divisors, whose sum is σ = 1265682. Its totient is φ = 1265680.

The previous prime is 1265657. The next prime is 1265729. The reversal of 1265681 is 1865621.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 640000 + 625681 = 800^2 + 791^2 .

It is a cyclic number.

It is not a de Polignac number, because 1265681 - 2⁶ = 1265617 is a prime.

It is a super-2 number, since 2×1265681² = 3203896787522, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1265611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 632840 + 632841.

It is an arithmetic number, because the mean of its divisors is an integer number (632841).

2^1265681 is an apocalyptic number.

It is an amenable number.

1265681 is a deficient number, since it is larger than the sum of its proper divisors (1).

1265681 is an equidigital number, since it uses as much as digits as its factorization.

1265681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2880, while the sum is 29.

The square root of 1265681 is about 1125.0248886136. The cubic root of 1265681 is about 108.1703131268.

It can be divided in two parts, 126 and 5681, that multiplied together give a triangular number (715806 = T₁₁₉₆).

The spelling of 1265681 in words is "one million, two hundred sixty-five thousand, six hundred eighty-one".