877975817661 has 48 divisors (see below), whose sum is σ = 1379349270000. Its totient is φ = 535892557824.

The previous prime is 877975817629. The next prime is 877975817681. The reversal of 877975817661 is 166718579778.

It can be written as a sum of positive squares in 8 ways, for example, as 343806322500 + 534169495161 = 586350^2 + 730869^2 .

It is not a de Polignac number, because 877975817661 - 2⁵ = 877975817629 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 877975817661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (877975817681) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 36495765 + ... + 36519813.

It is an arithmetic number, because the mean of its divisors is an integer number (28736443125).

Almost surely, 2^877975817661 is an apocalyptic number.

It is an amenable number.

877975817661 is a deficient number, since it is larger than the sum of its proper divisors (501373452339).

877975817661 is a wasteful number, since it uses less digits than its factorization.

877975817661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30558 (or 30555 counting only the distinct ones).

The product of its digits is 248935680, while the sum is 72.

The spelling of 877975817661 in words is "eight hundred seventy-seven billion, nine hundred seventy-five million, eight hundred seventeen thousand, six hundred sixty-one".