40021240 has 64 divisors (see below), whose sum is σ = 105048000. Its totient is φ = 13716864.

The previous prime is 40021231. The next prime is 40021243. The reversal of 40021240 is 4212004.

40021240 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×40021240² = 3203399302275200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 40021240.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40021243) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12262 + ... + 15178.

It is an arithmetic number, because the mean of its divisors is an integer number (1641375).

Almost surely, 2^40021240 is an apocalyptic number.

40021240 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 40021240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52524000).

40021240 is an abundant number, since it is smaller than the sum of its proper divisors (65026760).

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

40021240 is a wasteful number, since it uses less digits than its factorization.

40021240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2949 (or 2931 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 13.

The square root of 40021240 is about 6326.2342669237. The cubic root of 40021240 is about 342.0557117726.

Adding to 40021240 its reverse (4212004), we get a palindrome (44233244).

The spelling of 40021240 in words is "forty million, twenty-one thousand, two hundred forty".