1290656 has 24 divisors (see below), whose sum is σ = 2592324. Its totient is φ = 632320.

The previous prime is 1290649. The next prime is 1290659. The reversal of 1290656 is 6560921.

It can be written as a sum of positive squares in 2 ways, for example, as 1210000 + 80656 = 1100^2 + 284^2 .

It is not an unprimeable number, because it can be changed into a prime (1290659) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1316 + ... + 2076.

2^1290656 is an apocalyptic number.

1290656 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1290656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1296162).

1290656 is an abundant number, since it is smaller than the sum of its proper divisors (1301668).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1290656 is an equidigital number, since it uses as much as digits as its factorization.

1290656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 824 (or 816 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 29.

The square root of 1290656 is about 1136.0704203525. The cubic root of 1290656 is about 108.8771727564.

It can be divided in two parts, 129065 and 6, that multiplied together give a triangular number (774390 = T₁₂₄₄).

The spelling of 1290656 in words is "one million, two hundred ninety thousand, six hundred fifty-six".