861620587 has 2 divisors, whose sum is σ = 861620588. Its totient is φ = 861620586.

The previous prime is 861620581. The next prime is 861620621. The reversal of 861620587 is 785026168.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 861620587 - 2¹¹ = 861618539 is a prime.

It is not a weakly prime, because it can be changed into another prime (861620581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430810293 + 430810294.

It is an arithmetic number, because the mean of its divisors is an integer number (430810294).

Almost surely, 2^861620587 is an apocalyptic number.

861620587 is a deficient number, since it is larger than the sum of its proper divisors (1).

861620587 is an equidigital number, since it uses as much as digits as its factorization.

861620587 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 161280, while the sum is 43.

The square root of 861620587 is about 29353.3743716119. The cubic root of 861620587 is about 951.5655026362.

The spelling of 861620587 in words is "eight hundred sixty-one million, six hundred twenty thousand, five hundred eighty-seven".