861945544 has 8 divisors (see below), whose sum is σ = 1616147910. Its totient is φ = 430972768.

The previous prime is 861945523. The next prime is 861945551. The reversal of 861945544 is 445549168.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 789048100 + 72897444 = 28090^2 + 8538^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 861945494 and 861945503.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 53871589 + ... + 53871604.

Almost surely, 2^861945544 is an apocalyptic number.

It is an amenable number.

861945544 is a deficient number, since it is larger than the sum of its proper divisors (754202366).

861945544 is a wasteful number, since it uses less digits than its factorization.

861945544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107743199 (or 107743195 counting only the distinct ones).

The product of its digits is 691200, while the sum is 46.

The square root of 861945544 is about 29358.9091077989. The cubic root of 861945544 is about 951.6851140639.

The spelling of 861945544 in words is "eight hundred sixty-one million, nine hundred forty-five thousand, five hundred forty-four".