78341816450321 has 4 divisors (see below), whose sum is σ = 80163719158512. Its totient is φ = 76519913742132.

The previous prime is 78341816450309. The next prime is 78341816450347. The reversal of 78341816450321 is 12305461814387.

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 not a de Polignac number, because 78341816450321 - 2¹⁰ = 78341816449297 is a prime.

It is a super-2 number, since 2×78341816450321² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78341816450351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 910951354031 + ... + 910951354116.

It is an arithmetic number, because the mean of its divisors is an integer number (20040929789628).

Almost surely, 2^{78341816450321} is an apocalyptic number.

It is an amenable number.

78341816450321 is a deficient number, since it is larger than the sum of its proper divisors (1821902708191).

78341816450321 is a wasteful number, since it uses less digits than its factorization.

78341816450321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1821902708190.

The product of its (nonzero) digits is 3870720, while the sum is 53.

The spelling of 78341816450321 in words is "seventy-eight trillion, three hundred forty-one billion, eight hundred sixteen million, four hundred fifty thousand, three hundred twenty-one".