405321420 has 96 divisors (see below), whose sum is σ = 1324689408. Its totient is φ = 90669312.

The previous prime is 405321419. The next prime is 405321431. The reversal of 405321420 is 24123504.

It is a Harshad number since it is a multiple of its sum of digits (21).

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 31 ways as a sum of consecutive naturals, for example, 9474 + ... + 30006.

It is an arithmetic number, because the mean of its divisors is an integer number (13798848).

Almost surely, 2^405321420 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 405321420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (662344704).

405321420 is an abundant number, since it is smaller than the sum of its proper divisors (919367988).

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

405321420 is a wasteful number, since it uses less digits than its factorization.

405321420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20599 (or 20597 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 21.

The square root of 405321420 is about 20132.5959577994. The cubic root of 405321420 is about 740.0592964415.

Adding to 405321420 its reverse (24123504), we get a palindrome (429444924).

The spelling of 405321420 in words is "four hundred five million, three hundred twenty-one thousand, four hundred twenty".