1640040 has 64 divisors (see below), whose sum is σ = 5011200. Its totient is φ = 429312.

The previous prime is 1640033. The next prime is 1640053. The reversal of 1640040 is 400461.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9394 + ... + 9566.

It is an arithmetic number, because the mean of its divisors is an integer number (78300).

2^1640040 is an apocalyptic number.

1640040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1640040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2505600).

1640040 is an abundant number, since it is smaller than the sum of its proper divisors (3371160).

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

1640040 is a wasteful number, since it uses less digits than its factorization.

1640040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 266 (or 262 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 1640040 is about 1280.6404647675. The cubic root of 1640040 is about 117.9283295507.

The spelling of 1640040 in words is "one million, six hundred forty thousand, forty".