400444440 has 64 divisors (see below), whose sum is σ = 1310549760. Its totient is φ = 97077120.

The previous prime is 400444439. The next prime is 400444463. The reversal of 400444440 is 44444004.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 400444440.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 150364 + ... + 153003.

It is an arithmetic number, because the mean of its divisors is an integer number (20477340).

Almost surely, 2^400444440 is an apocalyptic number.

400444440 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

400444440 is an abundant number, since it is smaller than the sum of its proper divisors (910105320).

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

400444440 is a wasteful number, since it uses less digits than its factorization.

400444440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 303392 (or 303388 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 24.

The square root of 400444440 is about 20011.1079153554. The cubic root of 400444440 is about 737.0790872148.

Adding to 400444440 its reverse (44444004), we get a palindrome (444888444).

The spelling of 400444440 in words is "four hundred million, four hundred forty-four thousand, four hundred forty".