40028638 has 8 divisors (see below), whose sum is σ = 64661688. Its totient is φ = 18474744.

The previous prime is 40028633. The next prime is 40028641. The reversal of 40028638 is 83682004.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40028633) 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, 769756 + ... + 769807.

It is an arithmetic number, because the mean of its divisors is an integer number (8082711).

Almost surely, 2^40028638 is an apocalyptic number.

40028638 is a deficient number, since it is larger than the sum of its proper divisors (24633050).

40028638 is a wasteful number, since it uses less digits than its factorization.

40028638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1539578.

The product of its (nonzero) digits is 9216, while the sum is 31.

The square root of 40028638 is about 6326.8189479390. The cubic root of 40028638 is about 342.0767870171.

The spelling of 40028638 in words is "forty million, twenty-eight thousand, six hundred thirty-eight".