861255444 has 48 divisors (see below), whose sum is σ = 2298800000. Its totient is φ = 245846016.

The previous prime is 861255433. The next prime is 861255449. The reversal of 861255444 is 444552168.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861255449) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 100812 + ... + 109020.

Almost surely, 2^861255444 is an apocalyptic number.

861255444 is a gapful number since it is divisible by the number (84) formed by its first and last digit.

It is an amenable number.

861255444 is an abundant number, since it is smaller than the sum of its proper divisors (1437544556).

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

861255444 is a wasteful number, since it uses less digits than its factorization.

861255444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9472 (or 9470 counting only the distinct ones).

The product of its digits is 153600, while the sum is 39.

The square root of 861255444 is about 29347.1539335589. The cubic root of 861255444 is about 951.4310635023.

The spelling of 861255444 in words is "eight hundred sixty-one million, two hundred fifty-five thousand, four hundred forty-four".