878211117881 has 2 divisors, whose sum is σ = 878211117882. Its totient is φ = 878211117880.

The previous prime is 878211117821. The next prime is 878211117919. The reversal of 878211117881 is 188711112878.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 659897900281 + 218313217600 = 812341^2 + 467240^2 .

It is a cyclic number.

It is not a de Polignac number, because 878211117881 - 2¹⁰ = 878211116857 is a prime.

It is a super-2 number, since 2×878211117881² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (878211117821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 439105558940 + 439105558941.

It is an arithmetic number, because the mean of its divisors is an integer number (439105558941).

Almost surely, 2^878211117881 is an apocalyptic number.

It is an amenable number.

878211117881 is a deficient number, since it is larger than the sum of its proper divisors (1).

878211117881 is an equidigital number, since it uses as much as digits as its factorization.

878211117881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 401408, while the sum is 53.

The spelling of 878211117881 in words is "eight hundred seventy-eight billion, two hundred eleven million, one hundred seventeen thousand, eight hundred eighty-one".