9900078865487 has 4 divisors (see below), whose sum is σ = 9900422778360. Its totient is φ = 9899734952616.

The previous prime is 9900078865477. The next prime is 9900078865513. The reversal of 9900078865487 is 7845688700099.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 9900078865487 - 2²⁰ = 9900077816911 is a prime.

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 9900078865487.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9900078865477) 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 3 ways as a sum of consecutive naturals, for example, 171913253 + ... + 171970830.

It is an arithmetic number, because the mean of its divisors is an integer number (2475105694590).

Almost surely, 2^{9900078865487} is an apocalyptic number.

9900078865487 is a deficient number, since it is larger than the sum of its proper divisors (343912873).

9900078865487 is a wasteful number, since it uses less digits than its factorization.

9900078865487 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 343912872.

The product of its (nonzero) digits is 243855360, while the sum is 71.

The spelling of 9900078865487 in words is "nine trillion, nine hundred billion, seventy-eight million, eight hundred sixty-five thousand, four hundred eighty-seven".