861647 has 2 divisors, whose sum is σ = 861648. Its totient is φ = 861646.

The previous prime is 861617. The next prime is 861659. The reversal of 861647 is 746168.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 861647 - 2⁸ = 861391 is a prime.

It is a Chen prime.

It is a plaindrome in base 12.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 861647.

It is not a weakly prime, because it can be changed into another prime (861617) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430823 + 430824.

It is an arithmetic number, because the mean of its divisors is an integer number (430824).

2⁸⁶¹⁶⁴⁷ is an apocalyptic number.

861647 is a deficient number, since it is larger than the sum of its proper divisors (1).

861647 is an equidigital number, since it uses as much as digits as its factorization.

861647 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8064, while the sum is 32.

The square root of 861647 is about 928.2494276863. The cubic root of 861647 is about 95.1575225958.

The spelling of 861647 in words is "eight hundred sixty-one thousand, six hundred forty-seven".