891040878 has 128 divisors (see below), whose sum is σ = 2453068800. Its totient is φ = 233456256.

The previous prime is 891040867. The next prime is 891040889. The reversal of 891040878 is 878040198.

891040878 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (891040867) and next prime (891040889).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 879100 + ... + 880112.

It is an arithmetic number, because the mean of its divisors is an integer number (19164600).

Almost surely, 2^891040878 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 891040878, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1226534400).

891040878 is an abundant number, since it is smaller than the sum of its proper divisors (1562027922).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

891040878 is a wasteful number, since it uses less digits than its factorization.

891040878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1223 (or 1217 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 45.

The square root of 891040878 is about 29850.3078376086. The cubic root of 891040878 is about 962.2750145524.

The spelling of 891040878 in words is "eight hundred ninety-one million, forty thousand, eight hundred seventy-eight".