478481821 has 2 divisors, whose sum is σ = 478481822. Its totient is φ = 478481820.

The previous prime is 478481819. The next prime is 478481831. The reversal of 478481821 is 128184874.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 432432025 + 46049796 = 20795^2 + 6786^2 .

It is a cyclic number.

It is not a de Polignac number, because 478481821 - 2¹ = 478481819 is a prime.

Together with 478481819, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (478481831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 239240910 + 239240911.

It is an arithmetic number, because the mean of its divisors is an integer number (239240911).

Almost surely, 2^478481821 is an apocalyptic number.

It is an amenable number.

478481821 is a deficient number, since it is larger than the sum of its proper divisors (1).

478481821 is an equidigital number, since it uses as much as digits as its factorization.

478481821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 114688, while the sum is 43.

The square root of 478481821 is about 21874.2273234965. The cubic root of 478481821 is about 782.1471744809.

The spelling of 478481821 in words is "four hundred seventy-eight million, four hundred eighty-one thousand, eight hundred twenty-one".