78318121841 has 4 divisors (see below), whose sum is σ = 78347142000. Its totient is φ = 78289101684.

The previous prime is 78318121789. The next prime is 78318121873. The reversal of 78318121841 is 14812181387.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 78318121841 - 2¹⁰ = 78318120817 is a prime.

It is a super-2 number, since 2×78318121841² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 78318121792 and 78318121801.

It is not an unprimeable number, because it can be changed into a prime (78318121891) 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, 14506031 + ... + 14511428.

It is an arithmetic number, because the mean of its divisors is an integer number (19586785500).

Almost surely, 2^78318121841 is an apocalyptic number.

It is an amenable number.

78318121841 is a deficient number, since it is larger than the sum of its proper divisors (29020159).

78318121841 is a wasteful number, since it uses less digits than its factorization.

78318121841 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29020158.

The product of its digits is 86016, while the sum is 44.

The spelling of 78318121841 in words is "seventy-eight billion, three hundred eighteen million, one hundred twenty-one thousand, eight hundred forty-one".