78520315881 has 8 divisors (see below), whose sum is σ = 119650005184. Its totient is φ = 44868751920.

The previous prime is 78520315847. The next prime is 78520315931. The reversal of 78520315881 is 18851302587.

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

It is not a de Polignac number, because 78520315881 - 2¹⁸ = 78520053737 is a prime.

It is a super-2 number, since 2×78520315881² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 78520315881.

It is not an unprimeable number, because it can be changed into a prime (78520315801) 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 7 ways as a sum of consecutive naturals, for example, 1869531310 + ... + 1869531351.

It is an arithmetic number, because the mean of its divisors is an integer number (14956250648).

Almost surely, 2^78520315881 is an apocalyptic number.

It is an amenable number.

78520315881 is a deficient number, since it is larger than the sum of its proper divisors (41129689303).

78520315881 is a wasteful number, since it uses less digits than its factorization.

78520315881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3739062671.

The product of its (nonzero) digits is 537600, while the sum is 48.

The spelling of 78520315881 in words is "seventy-eight billion, five hundred twenty million, three hundred fifteen thousand, eight hundred eighty-one".