40638340 has 48 divisors (see below), whose sum is σ = 90417600. Its totient is φ = 15299712.

The previous prime is 40638331. The next prime is 40638343. The reversal of 40638340 is 4383604.

It is a junction number, because it is equal to n+sod(n) for n = 40638299 and 40638308.

It is not an unprimeable number, because it can be changed into a prime (40638343) 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 in 15 ways as a sum of consecutive naturals, for example, 86787 + ... + 87253.

It is an arithmetic number, because the mean of its divisors is an integer number (1883700).

Almost surely, 2^40638340 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 40638340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45208800).

40638340 is an abundant number, since it is smaller than the sum of its proper divisors (49779260).

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

40638340 is a wasteful number, since it uses less digits than its factorization.

40638340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 724 (or 722 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 28.

The square root of 40638340 is about 6374.8207817946. The cubic root of 40638340 is about 343.8048401762.

It can be divided in two parts, 4063 and 8340, that added together give a triangular number (12403 = T₁₅₇).

The spelling of 40638340 in words is "forty million, six hundred thirty-eight thousand, three hundred forty".