40438 has 4 divisors (see below), whose sum is σ = 60660. Its totient is φ = 20218.

The previous prime is 40433. The next prime is 40459. The reversal of 40438 is 83404.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40433) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10108 + ... + 10111.

It is an arithmetic number, because the mean of its divisors is an integer number (15165).

2⁴⁰⁴³⁸ is an apocalyptic number.

40438 is a deficient number, since it is larger than the sum of its proper divisors (20222).

40438 is a wasteful number, since it uses less digits than its factorization.

40438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20221.

The product of its (nonzero) digits is 384, while the sum is 19.

The square root of 40438 is about 201.0920187377. The cubic root of 40438 is about 34.3238943062.

The spelling of 40438 in words is "forty thousand, four hundred thirty-eight".