987221879 has 4 divisors (see below), whose sum is σ = 1128253584. Its totient is φ = 846190176.

The previous prime is 987221869. The next prime is 987221897. The reversal of 987221879 is 978122789.

It is a happy number.

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 987221879 - 2⁸ = 987221623 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 987221879.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (987221839) 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, 70515842 + ... + 70515855.

It is an arithmetic number, because the mean of its divisors is an integer number (282063396).

Almost surely, 2^987221879 is an apocalyptic number.

987221879 is a deficient number, since it is larger than the sum of its proper divisors (141031705).

987221879 is a wasteful number, since it uses less digits than its factorization.

987221879 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 141031704.

The product of its digits is 1016064, while the sum is 53.

The square root of 987221879 is about 31420.0871895671. The cubic root of 987221879 is about 995.7223541706.

The spelling of 987221879 in words is "nine hundred eighty-seven million, two hundred twenty-one thousand, eight hundred seventy-nine".