1640244 has 24 divisors (see below), whose sum is σ = 3900960. Its totient is φ = 536224.

The previous prime is 1640231. The next prime is 1640263. The reversal of 1640244 is 4420461.

It is a plaindrome in base 13.

It is a self number, because there is not a number n which added to its sum of digits gives 1640244.

It is a congruent number.

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, 654 + ... + 1925.

It is an arithmetic number, because the mean of its divisors is an integer number (162540).

2^1640244 is an apocalyptic number.

It is an amenable number.

1640244 is an abundant number, since it is smaller than the sum of its proper divisors (2260716).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1640244 is a wasteful number, since it uses less digits than its factorization.

1640244 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2639 (or 2637 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 21.

The square root of 1640244 is about 1280.7201099382. The cubic root of 1640244 is about 117.9332189400.

The spelling of 1640244 in words is "one million, six hundred forty thousand, two hundred forty-four".