478365991321 has 2 divisors, whose sum is σ = 478365991322. Its totient is φ = 478365991320.

The previous prime is 478365991307. The next prime is 478365991391. The reversal of 478365991321 is 123199563874.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 476424355225 + 1941636096 = 690235^2 + 44064^2 .

It is a cyclic number.

It is not a de Polignac number, because 478365991321 - 2²⁵ = 478332436889 is a prime.

It is not a weakly prime, because it can be changed into another prime (478365991391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 239182995660 + 239182995661.

It is an arithmetic number, because the mean of its divisors is an integer number (239182995661).

Almost surely, 2^478365991321 is an apocalyptic number.

It is an amenable number.

478365991321 is a deficient number, since it is larger than the sum of its proper divisors (1).

478365991321 is an equidigital number, since it uses as much as digits as its factorization.

478365991321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9797760, while the sum is 58.

The spelling of 478365991321 in words is "four hundred seventy-eight billion, three hundred sixty-five million, nine hundred ninety-one thousand, three hundred twenty-one".