861076566 has 96 divisors (see below), whose sum is σ = 2201472000. Its totient is φ = 238146048.

The previous prime is 861076501. The next prime is 861076577. The reversal of 861076566 is 665670168.

861076566 is a `hidden beast` number, since 8 + 6 + 10 + 76 + 566 = 666.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 573685 + ... + 575183.

It is an arithmetic number, because the mean of its divisors is an integer number (22932000).

Almost surely, 2^861076566 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 861076566, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1100736000).

861076566 is an abundant number, since it is smaller than the sum of its proper divisors (1340395434).

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

861076566 is a wasteful number, since it uses less digits than its factorization.

861076566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1658 (or 1655 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 45.

The square root of 861076566 is about 29344.1061543881. The cubic root of 861076566 is about 951.3651899488.

The spelling of 861076566 in words is "eight hundred sixty-one million, seventy-six thousand, five hundred sixty-six".