421356640 has 48 divisors (see below), whose sum is σ = 999425952. Its totient is φ = 167870464.

The previous prime is 421356601. The next prime is 421356641. The reversal of 421356640 is 46653124.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421356641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35997 + ... + 46243.

It is an arithmetic number, because the mean of its divisors is an integer number (20821374).

Almost surely, 2^421356640 is an apocalyptic number.

421356640 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 421356640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (499712976).

421356640 is an abundant number, since it is smaller than the sum of its proper divisors (578069312).

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

421356640 is a wasteful number, since it uses less digits than its factorization.

421356640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10519 (or 10511 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 421356640 is about 20526.9734739440. The cubic root of 421356640 is about 749.6926978081.

The spelling of 421356640 in words is "four hundred twenty-one million, three hundred fifty-six thousand, six hundred forty".