78604321 has 2 divisors, whose sum is σ = 78604322. Its totient is φ = 78604320.

The previous prime is 78604303. The next prime is 78604373. The reversal of 78604321 is 12340687.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 58354321 + 20250000 = 7639^2 + 4500^2 .

It is an emirp because it is prime and its reverse (12340687) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78604321 - 2⁷ = 78604193 is a prime.

It is not a weakly prime, because it can be changed into another prime (78604621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39302160 + 39302161.

It is an arithmetic number, because the mean of its divisors is an integer number (39302161).

Almost surely, 2^78604321 is an apocalyptic number.

It is an amenable number.

78604321 is a deficient number, since it is larger than the sum of its proper divisors (1).

78604321 is an equidigital number, since it uses as much as digits as its factorization.

78604321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 78604321 is about 8865.9077933396. The cubic root of 78604321 is about 428.3664739743.

The spelling of 78604321 in words is "seventy-eight million, six hundred four thousand, three hundred twenty-one".