1640144 has 20 divisors (see below), whose sum is σ = 3467040. Its totient is φ = 745440.

The previous prime is 1640131. The next prime is 1640147. The reversal of 1640144 is 4410461.

It is a happy number.

It is a plaindrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1640147) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4484 + ... + 4835.

It is an arithmetic number, because the mean of its divisors is an integer number (173352).

2^1640144 is an apocalyptic number.

It is an amenable number.

1640144 is an abundant number, since it is smaller than the sum of its proper divisors (1826896).

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

1640144 is a wasteful number, since it uses less digits than its factorization.

1640144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9338 (or 9332 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 1640144 is about 1280.6810688068. The cubic root of 1640144 is about 117.9308222312.

The spelling of 1640144 in words is "one million, six hundred forty thousand, one hundred forty-four".