400040440 has 64 divisors (see below), whose sum is σ = 963108000. Its totient is φ = 149091840.

The previous prime is 400040429. The next prime is 400040441. The reversal of 400040440 is 44040004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400040441) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42046 + ... + 50674.

Almost surely, 2^400040440 is an apocalyptic number.

400040440 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 400040440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (481554000).

400040440 is an abundant number, since it is smaller than the sum of its proper divisors (563067560).

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

400040440 is a wasteful number, since it uses less digits than its factorization.

400040440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8720 (or 8716 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 16.

The square root of 400040440 is about 20001.0109744483. The cubic root of 400040440 is about 736.8311292636.

Adding to 400040440 its reverse (44040004), we get a palindrome (444080444).

The spelling of 400040440 in words is "four hundred million, forty thousand, four hundred forty".