421978439 has 8 divisors (see below), whose sum is σ = 426238848. Its totient is φ = 417739000.

The previous prime is 421978423. The next prime is 421978441. The reversal of 421978439 is 934879124.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 421978439 - 2⁴ = 421978423 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 421978393 and 421978402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421978339) 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, 36884 + ... + 46950.

It is an arithmetic number, because the mean of its divisors is an integer number (53279856).

Almost surely, 2^421978439 is an apocalyptic number.

421978439 is a deficient number, since it is larger than the sum of its proper divisors (4260409).

421978439 is a wasteful number, since it uses less digits than its factorization.

421978439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10485.

The product of its digits is 435456, while the sum is 47.

The square root of 421978439 is about 20542.1137909418. The cubic root of 421978439 is about 750.0612921761.

The spelling of 421978439 in words is "four hundred twenty-one million, nine hundred seventy-eight thousand, four hundred thirty-nine".