878217640 has 16 divisors (see below), whose sum is σ = 1975989780. Its totient is φ = 351287040.

The previous prime is 878217629. The next prime is 878217649. The reversal of 878217640 is 46712878.

It can be written as a sum of positive squares in 2 ways, for example, as 844832356 + 33385284 = 29066^2 + 5778^2 .

It is not an unprimeable number, because it can be changed into a prime (878217649) 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, 10977681 + ... + 10977760.

Almost surely, 2^878217640 is an apocalyptic number.

It is an amenable number.

878217640 is an abundant number, since it is smaller than the sum of its proper divisors (1097772140).

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

878217640 is a wasteful number, since it uses less digits than its factorization.

878217640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21955452 (or 21955448 counting only the distinct ones).

The product of its (nonzero) digits is 150528, while the sum is 43.

The square root of 878217640 is about 29634.7370496180. The cubic root of 878217640 is about 957.6365617700.

The spelling of 878217640 in words is "eight hundred seventy-eight million, two hundred seventeen thousand, six hundred forty".