78004321 has 4 divisors (see below), whose sum is σ = 78178500. Its totient is φ = 77830144.

The previous prime is 78004319. The next prime is 78004327. The reversal of 78004321 is 12340087.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12340087 = 2593 ⋅4759.

It can be written as a sum of positive squares in 2 ways, for example, as 24641296 + 53363025 = 4964^2 + 7305^2 .

It is a cyclic number.

It is not a de Polignac number, because 78004321 - 2¹ = 78004319 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78004327) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 86416 + ... + 87313.

It is an arithmetic number, because the mean of its divisors is an integer number (19544625).

Almost surely, 2^78004321 is an apocalyptic number.

It is an amenable number.

78004321 is a deficient number, since it is larger than the sum of its proper divisors (174179).

78004321 is a wasteful number, since it uses less digits than its factorization.

78004321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174178.

The product of its (nonzero) digits is 1344, while the sum is 25.

The square root of 78004321 is about 8832.0054913932. The cubic root of 78004321 is about 427.2737578353.

It can be divided in two parts, 7800 and 4321, that added together give a palindrome (12121).

The spelling of 78004321 in words is "seventy-eight million, four thousand, three hundred twenty-one".