400442420 has 72 divisors (see below), whose sum is σ = 1004849664. Its totient is φ = 131300928.

The previous prime is 400442323. The next prime is 400442431. The reversal of 400442420 is 24244004.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 400442392 and 400442401.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 71357 + ... + 76763.

Almost surely, 2^400442420 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 400442420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (502424832).

400442420 is an abundant number, since it is smaller than the sum of its proper divisors (604407244).

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

400442420 is a wasteful number, since it uses less digits than its factorization.

400442420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5469 (or 5444 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 20.

The square root of 400442420 is about 20011.0574433237. The cubic root of 400442420 is about 737.0778478400.

Adding to 400442420 its reverse (24244004), we get a palindrome (424686424).

The spelling of 400442420 in words is "four hundred million, four hundred forty-two thousand, four hundred twenty".