861445256 has 32 divisors (see below), whose sum is σ = 1943112000. Its totient is φ = 349759296.

The previous prime is 861445241. The next prime is 861445307. The reversal of 861445256 is 652544168.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 403751 + ... + 405878.

It is an arithmetic number, because the mean of its divisors is an integer number (60722250).

Almost surely, 2^861445256 is an apocalyptic number.

It is an amenable number.

861445256 is an abundant number, since it is smaller than the sum of its proper divisors (1081666744).

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

861445256 is a wasteful number, since it uses less digits than its factorization.

861445256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 809661 (or 809657 counting only the distinct ones).

The product of its digits is 230400, while the sum is 41.

The square root of 861445256 is about 29350.3876635386. The cubic root of 861445256 is about 951.5009536334.

The spelling of 861445256 in words is "eight hundred sixty-one million, four hundred forty-five thousand, two hundred fifty-six".