40402440 has 192 divisors, whose sum is σ = 144471600. Its totient is φ = 9732096.

The previous prime is 40402403. The next prime is 40402441. The reversal of 40402440 is 4420404.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 4186116 + 36216324 = 2046^2 + 6018^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (40402441) 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 47 ways as a sum of consecutive naturals, for example, 416472 + ... + 416568.

Almost surely, 2^40402440 is an apocalyptic number.

40402440 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 40402440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72235800).

40402440 is an abundant number, since it is smaller than the sum of its proper divisors (104069160).

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

40402440 is a wasteful number, since it uses less digits than its factorization.

40402440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 216 (or 209 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 18.

The square root of 40402440 is about 6356.2913715468. The cubic root of 40402440 is about 343.1383021110.

Adding to 40402440 its reverse (4420404), we get a palindrome (44822844).

The spelling of 40402440 in words is "forty million, four hundred two thousand, four hundred forty".