78625321 has 2 divisors, whose sum is σ = 78625322. Its totient is φ = 78625320.

The previous prime is 78625243. The next prime is 78625361. The reversal of 78625321 is 12352687.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 52359696 + 26265625 = 7236^2 + 5125^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78625321 is a prime.

It is a super-2 number, since 2×78625321² = 12363882204706082, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (78625361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39312660 + 39312661.

It is an arithmetic number, because the mean of its divisors is an integer number (39312661).

Almost surely, 2^78625321 is an apocalyptic number.

It is an amenable number.

78625321 is a deficient number, since it is larger than the sum of its proper divisors (1).

78625321 is an equidigital number, since it uses as much as digits as its factorization.

78625321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20160, while the sum is 34.

The square root of 78625321 is about 8867.0920261380. The cubic root of 78625321 is about 428.4046181664.

The spelling of 78625321 in words is "seventy-eight million, six hundred twenty-five thousand, three hundred twenty-one".