861659 has 2 divisors, whose sum is σ = 861660. Its totient is φ = 861658.

The previous prime is 861647. The next prime is 861691. The reversal of 861659 is 956168.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-861659 is a prime.

It is a Chen prime.

It is a plaindrome in base 12.

It is not a weakly prime, because it can be changed into another prime (861059) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430829 + 430830.

It is an arithmetic number, because the mean of its divisors is an integer number (430830).

2⁸⁶¹⁶⁵⁹ is an apocalyptic number.

861659 is a deficient number, since it is larger than the sum of its proper divisors (1).

861659 is an equidigital number, since it uses as much as digits as its factorization.

861659 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12960, while the sum is 35.

The square root of 861659 is about 928.2558914437. The cubic root of 861659 is about 95.1579643409.

The spelling of 861659 in words is "eight hundred sixty-one thousand, six hundred fifty-nine".