40240640 has 80 divisors (see below), whose sum is σ = 105328080. Its totient is φ = 14622720.

The previous prime is 40240637. The next prime is 40240657. The reversal of 40240640 is 4604204.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27446 + ... + 28874.

It is an arithmetic number, because the mean of its divisors is an integer number (1316601).

Almost surely, 2^40240640 is an apocalyptic number.

40240640 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 40240640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52664040).

40240640 is an abundant number, since it is smaller than the sum of its proper divisors (65087440).

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

40240640 is a wasteful number, since it uses less digits than its factorization.

40240640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1463 (or 1447 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 40240640 is about 6343.5510559938. The cubic root of 40240640 is about 342.6796329801.

Adding to 40240640 its reverse (4604204), we get a palindrome (44844844).

The spelling of 40240640 in words is "forty million, two hundred forty thousand, six hundred forty".