421637640 has 64 divisors (see below), whose sum is σ = 1266883200. Its totient is φ = 112261632.

The previous prime is 421637609. The next prime is 421637651. The reversal of 421637640 is 46736124.

It is a happy number.

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 15 ways as a sum of consecutive naturals, for example, 86796 + ... + 91524.

It is an arithmetic number, because the mean of its divisors is an integer number (19795050).

Almost surely, 2^421637640 is an apocalyptic number.

421637640 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

421637640 is an abundant number, since it is smaller than the sum of its proper divisors (845245560).

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

421637640 is a wasteful number, since it uses less digits than its factorization.

421637640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5486 (or 5482 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 33.

The square root of 421637640 is about 20533.8169856459. The cubic root of 421637640 is about 749.8593158345.

The spelling of 421637640 in words is "four hundred twenty-one million, six hundred thirty-seven thousand, six hundred forty".