421407840 has 576 divisors, whose sum is σ = 1737469440. Its totient is φ = 85155840.

The previous prime is 421407809. The next prime is 421407851. The reversal of 421407840 is 48704124.

It is a super-2 number, since 2×421407840² = 355169135226931200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 421407798 and 421407807.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 10278220 + ... + 10278260.

It is an arithmetic number, because the mean of its divisors is an integer number (3016440).

Almost surely, 2^421407840 is an apocalyptic number.

421407840 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 421407840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (868734720).

421407840 is an abundant number, since it is smaller than the sum of its proper divisors (1316061600).

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

421407840 is a wasteful number, since it uses less digits than its factorization.

421407840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115 (or 100 counting only the distinct ones).

The product of its (nonzero) digits is 7168, while the sum is 30.

The square root of 421407840 is about 20528.2205755881. The cubic root of 421407840 is about 749.7230621976.

The spelling of 421407840 in words is "four hundred twenty-one million, four hundred seven thousand, eight hundred forty".