855239561 has 8 divisors (see below), whose sum is σ = 933936384. Its totient is φ = 776700720.

The previous prime is 855239531. The next prime is 855239653. The reversal of 855239561 is 165932558.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 855239561 - 2¹⁰ = 855238537 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (855239531) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28025 + ... + 49958.

It is an arithmetic number, because the mean of its divisors is an integer number (116742048).

Almost surely, 2^855239561 is an apocalyptic number.

It is an amenable number.

855239561 is a deficient number, since it is larger than the sum of its proper divisors (78696823).

855239561 is a wasteful number, since it uses less digits than its factorization.

855239561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78991.

The product of its digits is 324000, while the sum is 44.

The square root of 855239561 is about 29244.4791541925. The cubic root of 855239561 is about 949.2106318193.

The spelling of 855239561 in words is "eight hundred fifty-five million, two hundred thirty-nine thousand, five hundred sixty-one".