400840448 has 36 divisors (see below), whose sum is σ = 806480640. Its totient is φ = 198825984.

The previous prime is 400840421. The next prime is 400840463. The reversal of 400840448 is 844048004.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 26348 + ... + 38676.

It is an arithmetic number, because the mean of its divisors is an integer number (22402240).

Almost surely, 2^400840448 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 400840448, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (403240320).

400840448 is an abundant number, since it is smaller than the sum of its proper divisors (405640192).

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

400840448 is a wasteful number, since it uses less digits than its factorization.

400840448 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12472 (or 12458 counting only the distinct ones).

The product of its (nonzero) digits is 16384, while the sum is 32.

The square root of 400840448 is about 20021.0001748164. Note that the first 3 decimals coincide. The cubic root of 400840448 is about 737.3219782132.

The spelling of 400840448 in words is "four hundred million, eight hundred forty thousand, four hundred forty-eight".