421111440 has 320 divisors, whose sum is σ = 1580851200. Its totient is φ = 102643200.

The previous prime is 421111433. The next prime is 421111469. The reversal of 421111440 is 44111124.

421111440 is a `hidden beast` number, since 4 + 211 + 11 + 440 = 666.

It is a Cunningham number, because it is equal to 20521²-1.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1272075 + ... + 1272405.

It is an arithmetic number, because the mean of its divisors is an integer number (4940160).

Almost surely, 2^421111440 is an apocalyptic number.

421111440 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 421111440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (790425600).

421111440 is an abundant number, since it is smaller than the sum of its proper divisors (1159739760).

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

421111440 is a wasteful number, since it uses less digits than its factorization.

421111440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 403 (or 391 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The square root of 421111440 is about 20520.9999756347. Note that the first 4 decimals coincide. The cubic root of 421111440 is about 749.5472467410.

Adding to 421111440 its reverse (44111124), we get a palindrome (465222564).

It can be divided in two parts, 4211 and 11440, that added together give a palindrome (15651).

The spelling of 421111440 in words is "four hundred twenty-one million, one hundred eleven thousand, four hundred forty".