1641659 has 2 divisors, whose sum is σ = 1641660. Its totient is φ = 1641658.

The previous prime is 1641641. The next prime is 1641709. The reversal of 1641659 is 9561461.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1641659 - 2⁸ = 1641403 is a prime.

It is not a weakly prime, because it can be changed into another prime (1641359) 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, 820829 + 820830.

It is an arithmetic number, because the mean of its divisors is an integer number (820830).

2^1641659 is an apocalyptic number.

1641659 is a deficient number, since it is larger than the sum of its proper divisors (1).

1641659 is an equidigital number, since it uses as much as digits as its factorization.

1641659 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6480, while the sum is 32.

The square root of 1641659 is about 1281.2724144381. The cubic root of 1641659 is about 117.9671219327.

The spelling of 1641659 in words is "one million, six hundred forty-one thousand, six hundred fifty-nine".