78518755447 has 16 divisors (see below), whose sum is σ = 86031770400. Its totient is φ = 71068631040.

The previous prime is 78518755421. The next prime is 78518755453. The reversal of 78518755447 is 74455781587.

It is a happy number.

It is not a de Polignac number, because 78518755447 - 2¹¹ = 78518753399 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78518755247) 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, 4284079 + ... + 4302367.

It is an arithmetic number, because the mean of its divisors is an integer number (5376985650).

Almost surely, 2^78518755447 is an apocalyptic number.

78518755447 is a deficient number, since it is larger than the sum of its proper divisors (7513014953).

78518755447 is a wasteful number, since it uses less digits than its factorization.

78518755447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19986.

The product of its digits is 43904000, while the sum is 61.

The spelling of 78518755447 in words is "seventy-eight billion, five hundred eighteen million, seven hundred fifty-five thousand, four hundred forty-seven".