871830661 has 4 divisors (see below), whose sum is σ = 938894572. Its totient is φ = 804766752.

The previous prime is 871830647. The next prime is 871830691. The reversal of 871830661 is 166038178.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 244328161 + 627502500 = 15631^2 + 25050^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-871830661 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (871830611) 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, 33531936 + ... + 33531961.

It is an arithmetic number, because the mean of its divisors is an integer number (234723643).

Almost surely, 2^871830661 is an apocalyptic number.

It is an amenable number.

871830661 is a deficient number, since it is larger than the sum of its proper divisors (67063911).

871830661 is a wasteful number, since it uses less digits than its factorization.

871830661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67063910.

The product of its (nonzero) digits is 48384, while the sum is 40.

The square root of 871830661 is about 29526.7787101810. The cubic root of 871830661 is about 955.3093890803.

The spelling of 871830661 in words is "eight hundred seventy-one million, eight hundred thirty thousand, six hundred sixty-one".