1986641 has 4 divisors (see below), whose sum is σ = 2040372. Its totient is φ = 1932912.

The previous prime is 1986631. The next prime is 1986679. The reversal of 1986641 is 1466891.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1466891 = 929 ⋅1579.

It can be written as a sum of positive squares in 2 ways, for example, as 1123600 + 863041 = 1060^2 + 929^2 .

It is a cyclic number.

It is not a de Polignac number, because 1986641 - 2⁶ = 1986577 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1986601) 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, 26810 + ... + 26883.

It is an arithmetic number, because the mean of its divisors is an integer number (510093).

2^1986641 is an apocalyptic number.

It is an amenable number.

1986641 is a deficient number, since it is larger than the sum of its proper divisors (53731).

1986641 is an equidigital number, since it uses as much as digits as its factorization.

1986641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53730.

The product of its digits is 10368, while the sum is 35.

The square root of 1986641 is about 1409.4825291574. The cubic root of 1986641 is about 125.7109566587.

The spelling of 1986641 in words is "one million, nine hundred eighty-six thousand, six hundred forty-one".