1640345 has 8 divisors (see below), whose sum is σ = 2249664. Its totient is φ = 1124784.

The previous prime is 1640333. The next prime is 1640393. The reversal of 1640345 is 5430461.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1640345 - 2⁶ = 1640281 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1640345.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23399 + ... + 23468.

It is an arithmetic number, because the mean of its divisors is an integer number (281208).

2^1640345 is an apocalyptic number.

It is an amenable number.

1640345 is a deficient number, since it is larger than the sum of its proper divisors (609319).

1640345 is an equidigital number, since it uses as much as digits as its factorization.

1640345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46879.

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 1640345 is about 1280.7595402729. The cubic root of 1640345 is about 117.9356395170.

The spelling of 1640345 in words is "one million, six hundred forty thousand, three hundred forty-five".