17987878971 has 12 divisors (see below), whose sum is σ = 25998681072. Its totient is φ = 11984447376.

The previous prime is 17987878969. The next prime is 17987879003.

17987878971 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 17987878971 - 2¹ = 17987878969 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 17987878971.

It is not an unprimeable number, because it can be changed into a prime (17987878771) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 607396 + ... + 636321.

It is an arithmetic number, because the mean of its divisors is an integer number (2166556756).

Almost surely, 2^17987878971 is an apocalyptic number.

17987878971 is a deficient number, since it is larger than the sum of its proper divisors (8010802101).

17987878971 is a wasteful number, since it uses less digits than its factorization.

17987878971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1245330 (or 1245327 counting only the distinct ones).

The product of its digits is 99574272, while the sum is 72.

The spelling of 17987878971 in words is "seventeen billion, nine hundred eighty-seven million, eight hundred seventy-eight thousand, nine hundred seventy-one".