861920766 has 48 divisors (see below), whose sum is σ = 2135952000. Its totient is φ = 246070224.

The previous prime is 861920753. The next prime is 861920777. The reversal of 861920766 is 667029168.

861920766 is a `hidden beast` number, since 8 + 619 + 20 + 7 + 6 + 6 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 262845 + ... + 266103.

It is an arithmetic number, because the mean of its divisors is an integer number (44499000).

Almost surely, 2^861920766 is an apocalyptic number.

861920766 is an abundant number, since it is smaller than the sum of its proper divisors (1274031234).

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

861920766 is a wasteful number, since it uses less digits than its factorization.

861920766 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5373 (or 5370 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 45.

The square root of 861920766 is about 29358.4871204223. The cubic root of 861920766 is about 951.6759947408.

The spelling of 861920766 in words is "eight hundred sixty-one million, nine hundred twenty thousand, seven hundred sixty-six".