861106009 has 2 divisors, whose sum is σ = 861106010. Its totient is φ = 861106008.

The previous prime is 861105989. The next prime is 861106027. The reversal of 861106009 is 900601168.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 791015625 + 70090384 = 28125^2 + 8372^2 .

It is a cyclic number.

It is not a de Polignac number, because 861106009 - 2¹¹ = 861103961 is a prime.

It is not a weakly prime, because it can be changed into another prime (861106079) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430553004 + 430553005.

It is an arithmetic number, because the mean of its divisors is an integer number (430553005).

Almost surely, 2^861106009 is an apocalyptic number.

It is an amenable number.

861106009 is a deficient number, since it is larger than the sum of its proper divisors (1).

861106009 is an equidigital number, since it uses as much as digits as its factorization.

861106009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2592, while the sum is 31.

The square root of 861106009 is about 29344.6078351714. The cubic root of 861106009 is about 951.3760332455.

The spelling of 861106009 in words is "eight hundred sixty-one million, one hundred six thousand, nine".