879991887 has 4 divisors (see below), whose sum is σ = 1173322520. Its totient is φ = 586661256.

The previous prime is 879991883. The next prime is 879991919. The reversal of 879991887 is 788199978.

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

It is not a de Polignac number, because 879991887 - 2² = 879991883 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 (879991883) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 146665312 + ... + 146665317.

It is an arithmetic number, because the mean of its divisors is an integer number (293330630).

Almost surely, 2^879991887 is an apocalyptic number.

879991887 is a deficient number, since it is larger than the sum of its proper divisors (293330633).

879991887 is a wasteful number, since it uses less digits than its factorization.

879991887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 293330632.

The product of its digits is 18289152, while the sum is 66.

The square root of 879991887 is about 29664.6572034804. The cubic root of 879991887 is about 958.2810264952.

The spelling of 879991887 in words is "eight hundred seventy-nine million, nine hundred ninety-one thousand, eight hundred eighty-seven".