120643866 has 96 divisors (see below), whose sum is σ = 319258368. Its totient is φ = 32140800.

The previous prime is 120643843. The next prime is 120643867. The reversal of 120643866 is 668346021.

120643866 is a `hidden beast` number, since 1 + 2 + 0 + 643 + 8 + 6 + 6 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 120643866.

It is not an unprimeable number, because it can be changed into a prime (120643867) 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, 323256 + ... + 323628.

It is an arithmetic number, because the mean of its divisors is an integer number (3325608).

Almost surely, 2^120643866 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 120643866, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (159629184).

120643866 is an abundant number, since it is smaller than the sum of its proper divisors (198614502).

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

120643866 is a wasteful number, since it uses less digits than its factorization.

120643866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 556 (or 553 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 36.

The square root of 120643866 is about 10983.8001620568. The cubic root of 120643866 is about 494.1230140523.

Adding to 120643866 its reverse (668346021), we get a palindrome (788989887).

The spelling of 120643866 in words is "one hundred twenty million, six hundred forty-three thousand, eight hundred sixty-six".