1640445 has 8 divisors (see below), whose sum is σ = 2624736. Its totient is φ = 874896.

The previous prime is 1640423. The next prime is 1640447. The reversal of 1640445 is 5440461.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1640445 - 2⁸ = 1640189 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1640447) 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 7 ways as a sum of consecutive naturals, for example, 54667 + ... + 54696.

It is an arithmetic number, because the mean of its divisors is an integer number (328092).

2^1640445 is an apocalyptic number.

1640445 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1640445 is a deficient number, since it is larger than the sum of its proper divisors (984291).

1640445 is a wasteful number, since it uses less digits than its factorization.

1640445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109371.

The product of its (nonzero) digits is 1920, while the sum is 24.

The square root of 1640445 is about 1280.7985790123. The cubic root of 1640445 is about 117.9380360299.

The spelling of 1640445 in words is "one million, six hundred forty thousand, four hundred forty-five".