1640238 has 16 divisors (see below), whose sum is σ = 3293136. Its totient is φ = 544640.

The previous prime is 1640231. The next prime is 1640263. The reversal of 1640238 is 8320461.

It is a happy number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1640231) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2470 + ... + 3062.

It is an arithmetic number, because the mean of its divisors is an integer number (205821).

2^1640238 is an apocalyptic number.

1640238 is an abundant number, since it is smaller than the sum of its proper divisors (1652898).

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

1640238 is a wasteful number, since it uses less digits than its factorization.

1640238 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1059.

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 1640238 is about 1280.7177675038. The cubic root of 1640238 is about 117.9330751402.

Adding to 1640238 its reverse (8320461), we get a palindrome (9960699).

The spelling of 1640238 in words is "one million, six hundred forty thousand, two hundred thirty-eight".