421643340 has 96 divisors (see below), whose sum is σ = 1320721920. Its totient is φ = 111672000.

The previous prime is 421643309. The next prime is 421643353. The reversal of 421643340 is 43346124.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 78955 + ... + 84125.

It is an arithmetic number, because the mean of its divisors is an integer number (13757520).

Almost surely, 2^421643340 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 421643340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (660360960).

421643340 is an abundant number, since it is smaller than the sum of its proper divisors (899078580).

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

421643340 is a wasteful number, since it uses less digits than its factorization.

421643340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5340 (or 5332 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 27.

The square root of 421643340 is about 20533.9557806089. The cubic root of 421643340 is about 749.8626948646.

Adding to 421643340 its reverse (43346124), we get a palindrome (464989464).

The spelling of 421643340 in words is "four hundred twenty-one million, six hundred forty-three thousand, three hundred forty".