40040644 has 72 divisors (see below), whose sum is σ = 88166232. Its totient is φ = 15805440.

The previous prime is 40040633. The next prime is 40040647. The reversal of 40040644 is 44604004.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 11289600 + 28751044 = 3360^2 + 5362^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40040647) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 203154 + ... + 203350.

It is an arithmetic number, because the mean of its divisors is an integer number (1224531).

Almost surely, 2^40040644 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 40040644, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44083116).

40040644 is an abundant number, since it is smaller than the sum of its proper divisors (48125588).

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

40040644 is a wasteful number, since it uses less digits than its factorization.

40040644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 293 (or 284 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 22.

The square root of 40040644 is about 6327.7676948510. The cubic root of 40040644 is about 342.1109838952.

Adding to 40040644 its reverse (44604004), we get a palindrome (84644648).

The spelling of 40040644 in words is "forty million, forty thousand, six hundred forty-four".