987885391 has 4 divisors (see below), whose sum is σ = 1006524792. Its totient is φ = 969245992.

The previous prime is 987885329. The next prime is 987885467. The reversal of 987885391 is 193588789.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 193588789 = 79 ⋅2450491.

It is a cyclic number.

It is not a de Polignac number, because 987885391 - 2⁷ = 987885263 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (987885191) 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, 9319621 + ... + 9319726.

It is an arithmetic number, because the mean of its divisors is an integer number (251631198).

Almost surely, 2^987885391 is an apocalyptic number.

987885391 is a deficient number, since it is larger than the sum of its proper divisors (18639401).

987885391 is a wasteful number, since it uses less digits than its factorization.

987885391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18639400.

The product of its digits is 4354560, while the sum is 58.

The square root of 987885391 is about 31430.6441391200. The cubic root of 987885391 is about 995.9453792700.

The spelling of 987885391 in words is "nine hundred eighty-seven million, eight hundred eighty-five thousand, three hundred ninety-one".