861311668 has 24 divisors (see below), whose sum is σ = 1732150784. Its totient is φ = 367092000.

The previous prime is 861311653. The next prime is 861311683. The reversal of 861311668 is 866113168.

861311668 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 (861311653) and next prime (861311683).

It is a self number, because there is not a number n which added to its sum of digits gives 861311668.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 79908 + ... + 90043.

Almost surely, 2^861311668 is an apocalyptic number.

It is an amenable number.

861311668 is an abundant number, since it is smaller than the sum of its proper divisors (870839116).

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

861311668 is a wasteful number, since it uses less digits than its factorization.

861311668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170143 (or 170141 counting only the distinct ones).

The product of its digits is 41472, while the sum is 40.

The square root of 861311668 is about 29348.1118302353. Note that the first 3 decimals coincide. The cubic root of 861311668 is about 951.4517666500.

The spelling of 861311668 in words is "eight hundred sixty-one million, three hundred eleven thousand, six hundred sixty-eight".