478694221 has 2 divisors, whose sum is σ = 478694222. Its totient is φ = 478694220.

The previous prime is 478694173. The next prime is 478694269. The reversal of 478694221 is 122496874.

It is a balanced prime because it is at equal distance from previous prime (478694173) and next prime (478694269).

It can be written as a sum of positive squares in only one way, i.e., 309408100 + 169286121 = 17590^2 + 13011^2 .

It is a cyclic number.

It is not a de Polignac number, because 478694221 - 2²⁵ = 445139789 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (478694521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 239347110 + 239347111.

It is an arithmetic number, because the mean of its divisors is an integer number (239347111).

Almost surely, 2^478694221 is an apocalyptic number.

It is an amenable number.

478694221 is a deficient number, since it is larger than the sum of its proper divisors (1).

478694221 is an equidigital number, since it uses as much as digits as its factorization.

478694221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 193536, while the sum is 43.

The square root of 478694221 is about 21879.0818134583. The cubic root of 478694221 is about 782.2628901166.

The spelling of 478694221 in words is "four hundred seventy-eight million, six hundred ninety-four thousand, two hundred twenty-one".