400320420 has 96 divisors (see below), whose sum is σ = 1192060800. Its totient is φ = 100030464.

The previous prime is 400320397. The next prime is 400320461. The reversal of 400320420 is 24023004.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 400320420.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 273651 + ... + 275109.

It is an arithmetic number, because the mean of its divisors is an integer number (12417300).

Almost surely, 2^400320420 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 400320420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (596030400).

400320420 is an abundant number, since it is smaller than the sum of its proper divisors (791740380).

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

400320420 is a wasteful number, since it uses less digits than its factorization.

400320420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1757 (or 1755 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 15.

The square root of 400320420 is about 20008.0088964394. The cubic root of 400320420 is about 737.0029867808.

Adding to 400320420 its reverse (24023004), we get a palindrome (424343424).

The spelling of 400320420 in words is "four hundred million, three hundred twenty thousand, four hundred twenty".