9978858871 has 4 divisors (see below), whose sum is σ = 9979059544. Its totient is φ = 9978658200.

The previous prime is 9978858779. The next prime is 9978858889. The reversal of 9978858871 is 1788588799.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9978858871 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 9978858871.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9978858971) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36061 + ... + 145801.

It is an arithmetic number, because the mean of its divisors is an integer number (2494764886).

Almost surely, 2^9978858871 is an apocalyptic number.

9978858871 is a deficient number, since it is larger than the sum of its proper divisors (200673).

9978858871 is a wasteful number, since it uses less digits than its factorization.

9978858871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200672.

The product of its digits is 81285120, while the sum is 70.

The square root of 9978858871 is about 99894.2384274489. The cubic root of 9978858871 is about 2152.9153794735.

The spelling of 9978858871 in words is "nine billion, nine hundred seventy-eight million, eight hundred fifty-eight thousand, eight hundred seventy-one".