420643440 has 180 divisors, whose sum is σ = 1643437224. Its totient is φ = 96139008.

The previous prime is 420643439. The next prime is 420643453. The reversal of 420643440 is 44346024.

It is a tau number, because it is divible by the number of its divisors (180).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 29319 + ... + 41241.

Almost surely, 2^420643440 is an apocalyptic number.

420643440 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 420643440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (821718612).

420643440 is an abundant number, since it is smaller than the sum of its proper divisors (1222793784).

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

420643440 is a wasteful number, since it uses less digits than its factorization.

420643440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11956 (or 11940 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 27.

The square root of 420643440 is about 20509.5938526339. The cubic root of 420643440 is about 749.2694753427.

Adding to 420643440 its reverse (44346024), we get a palindrome (464989464).

The spelling of 420643440 in words is "four hundred twenty million, six hundred forty-three thousand, four hundred forty".