78329361921 has 16 divisors (see below), whose sum is σ = 104915720448. Its totient is φ = 51981530000.

The previous prime is 78329361919. The next prime is 78329361931. The reversal of 78329361921 is 12916392387.

It is a cyclic number.

It is not a de Polignac number, because 78329361921 - 2¹ = 78329361919 is a prime.

It is a super-2 number, since 2×78329361921² (a number of 23 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (78329361931) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1316506 + ... + 1374716.

It is an arithmetic number, because the mean of its divisors is an integer number (6557232528).

Almost surely, 2^78329361921 is an apocalyptic number.

It is an amenable number.

78329361921 is a deficient number, since it is larger than the sum of its proper divisors (26586358527).

78329361921 is a wasteful number, since it uses less digits than its factorization.

78329361921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60252.

The product of its digits is 979776, while the sum is 51.

The spelling of 78329361921 in words is "seventy-eight billion, three hundred twenty-nine million, three hundred sixty-one thousand, nine hundred twenty-one".