400422144 has 72 divisors (see below), whose sum is σ = 1083892320. Its totient is φ = 131196928.

The previous prime is 400422091. The next prime is 400422151. The reversal of 400422144 is 441224004.

It is a self number, because there is not a number n which added to its sum of digits gives 400422144.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40894 + ... + 49730.

It is an arithmetic number, because the mean of its divisors is an integer number (15054060).

Almost surely, 2^400422144 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 400422144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (541946160).

400422144 is an abundant number, since it is smaller than the sum of its proper divisors (683470176).

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

400422144 is an equidigital number, since it uses as much as digits as its factorization.

400422144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8915 (or 8901 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 21.

The square root of 400422144 is about 20010.5508170065. The cubic root of 400422144 is about 737.0654072310.

Adding to 400422144 its reverse (441224004), we get a palindrome (841646148).

The spelling of 400422144 in words is "four hundred million, four hundred twenty-two thousand, one hundred forty-four".