1640959 has 4 divisors (see below), whose sum is σ = 1737504. Its totient is φ = 1544416.

The previous prime is 1640953. The next prime is 1640971. The reversal of 1640959 is 9590461.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9590461 = 1237 ⋅7753.

It is not a de Polignac number, because 1640959 - 2⁵ = 1640927 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 (1640953) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 48247 + ... + 48280.

It is an arithmetic number, because the mean of its divisors is an integer number (434376).

2^1640959 is an apocalyptic number.

1640959 is a deficient number, since it is larger than the sum of its proper divisors (96545).

1640959 is an equidigital number, since it uses as much as digits as its factorization.

1640959 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96544.

The product of its (nonzero) digits is 9720, while the sum is 34.

The square root of 1640959 is about 1280.9992193596. Note that the first 3 decimals coincide. The cubic root of 1640959 is about 117.9503525701.

The spelling of 1640959 in words is "one million, six hundred forty thousand, nine hundred fifty-nine".