421443240 has 64 divisors (see below), whose sum is σ = 1270080000. Its totient is φ = 111873792.

The previous prime is 421443229. The next prime is 421443241. The reversal of 421443240 is 42344124.

It is a happy number.

It is a super-2 number, since 2×421443240² = 355228809083395200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 421443240.

It is not an unprimeable number, because it can be changed into a prime (421443241) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18886 + ... + 34634.

It is an arithmetic number, because the mean of its divisors is an integer number (19845000).

Almost surely, 2^421443240 is an apocalyptic number.

421443240 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 421443240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (635040000).

421443240 is an abundant number, since it is smaller than the sum of its proper divisors (848636760).

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

421443240 is a wasteful number, since it uses less digits than its factorization.

421443240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15986 (or 15982 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 24.

The square root of 421443240 is about 20529.0827851612. The cubic root of 421443240 is about 749.7440548883.

Adding to 421443240 its reverse (42344124), we get a palindrome (463787364).

The spelling of 421443240 in words is "four hundred twenty-one million, four hundred forty-three thousand, two hundred forty".