860555261 has 4 divisors (see below), whose sum is σ = 860623932. Its totient is φ = 860486592.

The previous prime is 860555219. The next prime is 860555279. The reversal of 860555261 is 162555068.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 8265625 + 852289636 = 2875^2 + 29194^2 .

It is a cyclic number.

It is not a de Polignac number, because 860555261 - 2¹⁸ = 860293117 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (860555561) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9596 + ... + 42581.

It is an arithmetic number, because the mean of its divisors is an integer number (215155983).

Almost surely, 2^860555261 is an apocalyptic number.

It is an amenable number.

860555261 is a deficient number, since it is larger than the sum of its proper divisors (68671).

860555261 is a wasteful number, since it uses less digits than its factorization.

860555261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68670.

The product of its (nonzero) digits is 72000, while the sum is 38.

The square root of 860555261 is about 29335.2221910794. Note that the first 3 decimals coincide. The cubic root of 860555261 is about 951.1731622909.

The spelling of 860555261 in words is "eight hundred sixty million, five hundred fifty-five thousand, two hundred sixty-one".