1286491 has 2 divisors, whose sum is σ = 1286492. Its totient is φ = 1286490.

The previous prime is 1286489. The next prime is 1286503. The reversal of 1286491 is 1946821.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1286491 - 2¹ = 1286489 is a prime.

Together with 1286489, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1286191) 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 as a sum of consecutive naturals, namely, 643245 + 643246.

It is an arithmetic number, because the mean of its divisors is an integer number (643246).

2^1286491 is an apocalyptic number.

1286491 is a deficient number, since it is larger than the sum of its proper divisors (1).

1286491 is an equidigital number, since it uses as much as digits as its factorization.

1286491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3456, while the sum is 31.

The square root of 1286491 is about 1134.2358661231. The cubic root of 1286491 is about 108.7599295113.

The spelling of 1286491 in words is "one million, two hundred eighty-six thousand, four hundred ninety-one".