878596991 has 4 divisors (see below), whose sum is σ = 897290592. Its totient is φ = 859903392.

The previous prime is 878596981. The next prime is 878597003. The reversal of 878596991 is 199695878.

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-878596991 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 (878596981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9346730 + ... + 9346823.

It is an arithmetic number, because the mean of its divisors is an integer number (224322648).

Almost surely, 2^878596991 is an apocalyptic number.

878596991 is a deficient number, since it is larger than the sum of its proper divisors (18693601).

878596991 is a wasteful number, since it uses less digits than its factorization.

878596991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18693600.

The product of its digits is 9797760, while the sum is 62.

The square root of 878596991 is about 29641.1368034359. The cubic root of 878596991 is about 957.7744274032.

The spelling of 878596991 in words is "eight hundred seventy-eight million, five hundred ninety-six thousand, nine hundred ninety-one".