91878868908 has 18 divisors (see below), whose sum is σ = 232249363164. Its totient is φ = 30626289624.

The previous prime is 91878868889. The next prime is 91878868909. The reversal of 91878868908 is 80986887819.

It is a tau number, because it is divible by the number of its divisors (18).

It is a super-2 number, since 2×91878868908² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (91878868909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1276095366 + ... + 1276095437.

It is an arithmetic number, because the mean of its divisors is an integer number (12902742398).

Almost surely, 2^91878868908 is an apocalyptic number.

It is an amenable number.

91878868908 is an abundant number, since it is smaller than the sum of its proper divisors (140370494256).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91878868908 is a wasteful number, since it uses less digits than its factorization.

91878868908 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2552190813 (or 2552190808 counting only the distinct ones).

The product of its (nonzero) digits is 111476736, while the sum is 72.

The spelling of 91878868908 in words is "ninety-one billion, eight hundred seventy-eight million, eight hundred sixty-eight thousand, nine hundred eight".