321328978 has 4 divisors (see below), whose sum is σ = 481993470. Its totient is φ = 160664488.

The previous prime is 321328967. The next prime is 321328993. The reversal of 321328978 is 879823123.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 879823123 = 14081 ⋅62483.

It can be written as a sum of positive squares in only one way, i.e., 172318129 + 149010849 = 13127^2 + 12207^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80332243 + ... + 80332246.

Almost surely, 2^321328978 is an apocalyptic number.

321328978 is a deficient number, since it is larger than the sum of its proper divisors (160664492).

321328978 is a wasteful number, since it uses less digits than its factorization.

321328978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160664491.

The product of its digits is 145152, while the sum is 43.

The square root of 321328978 is about 17925.6513968112. The cubic root of 321328978 is about 684.9359543723.

The spelling of 321328978 in words is "three hundred twenty-one million, three hundred twenty-eight thousand, nine hundred seventy-eight".