478516621 has 4 divisors (see below), whose sum is σ = 522018144. Its totient is φ = 435015100.

The previous prime is 478516607. The next prime is 478516657. The reversal of 478516621 is 126615874.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 478516621 - 2⁹ = 478516109 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (478516321) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21750745 + ... + 21750766.

It is an arithmetic number, because the mean of its divisors is an integer number (130504536).

Almost surely, 2^478516621 is an apocalyptic number.

It is an amenable number.

478516621 is a deficient number, since it is larger than the sum of its proper divisors (43501523).

478516621 is a wasteful number, since it uses less digits than its factorization.

478516621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43501522.

The product of its digits is 80640, while the sum is 40.

The square root of 478516621 is about 21875.0227657024. The cubic root of 478516621 is about 782.1661358852.

The spelling of 478516621 in words is "four hundred seventy-eight million, five hundred sixteen thousand, six hundred twenty-one".