1290661 has 4 divisors (see below), whose sum is σ = 1292992. Its totient is φ = 1288332.

The previous prime is 1290659. The next prime is 1290673. The reversal of 1290661 is 1660921.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1290661 - 2¹ = 1290659 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1290631) 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 3 ways as a sum of consecutive naturals, for example, 196 + ... + 1618.

It is an arithmetic number, because the mean of its divisors is an integer number (323248).

2^1290661 is an apocalyptic number.

It is an amenable number.

1290661 is a deficient number, since it is larger than the sum of its proper divisors (2331).

1290661 is an equidigital number, since it uses as much as digits as its factorization.

1290661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2330.

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 1290661 is about 1136.0726209182. The cubic root of 1290661 is about 108.8773133529.

The spelling of 1290661 in words is "one million, two hundred ninety thousand, six hundred sixty-one".