86540638878 has 24 divisors (see below), whose sum is σ = 190578567816. Its totient is φ = 28373979600.

The previous prime is 86540638859. The next prime is 86540638897. The reversal of 86540638878 is 87883604568.

86540638878 is a `hidden beast` number, since 8 + 6 + 540 + 6 + 3 + 8 + 87 + 8 = 666.

It is an interprime number because it is at equal distance from previous prime (86540638859) and next prime (86540638897).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 39407208 + ... + 39409403.

It is an arithmetic number, because the mean of its divisors is an integer number (7940773659).

Almost surely, 2^86540638878 is an apocalyptic number.

86540638878 is an abundant number, since it is smaller than the sum of its proper divisors (104037928938).

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

86540638878 is a wasteful number, since it uses less digits than its factorization.

86540638878 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78816680 (or 78816677 counting only the distinct ones).

The product of its (nonzero) digits is 61931520, while the sum is 63.

The spelling of 86540638878 in words is "eighty-six billion, five hundred forty million, six hundred thirty-eight thousand, eight hundred seventy-eight".