878220091 has 12 divisors (see below), whose sum is σ = 1022110320. Its totient is φ = 752386320.

The previous prime is 878220073. The next prime is 878220107. The reversal of 878220091 is 190022878.

878220091 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 878220091 - 2⁹ = 878219579 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 878220091.

It is not an unprimeable number, because it can be changed into a prime (878220001) 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, 147961 + ... + 153781.

It is an arithmetic number, because the mean of its divisors is an integer number (85175860).

Almost surely, 2^878220091 is an apocalyptic number.

878220091 is a deficient number, since it is larger than the sum of its proper divisors (143890229).

878220091 is a wasteful number, since it uses less digits than its factorization.

878220091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8914 (or 8907 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 37.

The square root of 878220091 is about 29634.7784030858. The cubic root of 878220091 is about 957.6374526521.

The spelling of 878220091 in words is "eight hundred seventy-eight million, two hundred twenty thousand, ninety-one".