478981421 has 2 divisors, whose sum is σ = 478981422. Its totient is φ = 478981420.

The previous prime is 478981387. The next prime is 478981427. The reversal of 478981421 is 124189874.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 441588196 + 37393225 = 21014^2 + 6115^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-478981421 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (478981427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 239490710 + 239490711.

It is an arithmetic number, because the mean of its divisors is an integer number (239490711).

Almost surely, 2^478981421 is an apocalyptic number.

It is an amenable number.

478981421 is a deficient number, since it is larger than the sum of its proper divisors (1).

478981421 is an equidigital number, since it uses as much as digits as its factorization.

478981421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 129024, while the sum is 44.

The square root of 478981421 is about 21885.6441760347. The cubic root of 478981421 is about 782.4193024125.

The spelling of 478981421 in words is "four hundred seventy-eight million, nine hundred eighty-one thousand, four hundred twenty-one".