400400420 has 48 divisors (see below), whose sum is σ = 969978240. Its totient is φ = 135992064.

The previous prime is 400400389. The next prime is 400400437. The reversal of 400400420 is 24004004.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a junction number, because it is equal to n+sod(n) for n = 400400395 and 400400404.

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, 1616 + ... + 28344.

It is an arithmetic number, because the mean of its divisors is an integer number (20207880).

Almost surely, 2^400400420 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 400400420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (484989120).

400400420 is an abundant number, since it is smaller than the sum of its proper divisors (569577820).

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

400400420 is a wasteful number, since it uses less digits than its factorization.

400400420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26852 (or 26850 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 14.

The square root of 400400420 is about 20010.0079960004. The cubic root of 400400420 is about 737.0520777164.

Adding to 400400420 its reverse (24004004), we get a palindrome (424404424).

The spelling of 400400420 in words is "four hundred million, four hundred thousand, four hundred twenty".