78347170549981 has 8 divisors (see below), whose sum is σ = 81049844254680. Its totient is φ = 75644566654272.

The previous prime is 78347170549961. The next prime is 78347170549993. The reversal of 78347170549981 is 18994507174387.

It can be written as a sum of positive squares in 4 ways, for example, as 29834427168100 + 48512743381881 = 5462090^2 + 6965109^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 78347170549981 - 2²¹ = 78347168452829 is a prime.

It is a super-2 number, since 2×78347170549981² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78347170549951) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15163830 + ... + 19663063.

It is an arithmetic number, because the mean of its divisors is an integer number (10131230531835).

Almost surely, 2^{78347170549981} is an apocalyptic number.

It is an amenable number.

78347170549981 is a deficient number, since it is larger than the sum of its proper divisors (2702673704699).

78347170549981 is a wasteful number, since it uses less digits than its factorization.

78347170549981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34904495.

The product of its (nonzero) digits is 426746880, while the sum is 73.

The spelling of 78347170549981 in words is "seventy-eight trillion, three hundred forty-seven billion, one hundred seventy million, five hundred forty-nine thousand, nine hundred eighty-one".