78644321 has 8 divisors (see below), whose sum is σ = 90006144. Its totient is φ = 67314240.

The previous prime is 78644281. The next prime is 78644323. The reversal of 78644321 is 12344687.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 78644321 - 2¹⁰ = 78643297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78644323) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2360 + ... + 12761.

It is an arithmetic number, because the mean of its divisors is an integer number (11250768).

Almost surely, 2^78644321 is an apocalyptic number.

It is an amenable number.

78644321 is a deficient number, since it is larger than the sum of its proper divisors (11361823).

78644321 is a wasteful number, since it uses less digits than its factorization.

78644321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15871.

The product of its digits is 32256, while the sum is 35.

The square root of 78644321 is about 8868.1633385950. The cubic root of 78644321 is about 428.4391237263.

The spelling of 78644321 in words is "seventy-eight million, six hundred forty-four thousand, three hundred twenty-one".