864205961 has 2 divisors, whose sum is σ = 864205962. Its totient is φ = 864205960.

The previous prime is 864205939. The next prime is 864205973. The reversal of 864205961 is 169502468.

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., 773118025 + 91087936 = 27805^2 + 9544^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-864205961 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (864205261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 432102980 + 432102981.

It is an arithmetic number, because the mean of its divisors is an integer number (432102981).

Almost surely, 2^864205961 is an apocalyptic number.

It is an amenable number.

864205961 is a deficient number, since it is larger than the sum of its proper divisors (1).

864205961 is an equidigital number, since it uses as much as digits as its factorization.

864205961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 103680, while the sum is 41.

The square root of 864205961 is about 29397.3801723895. The cubic root of 864205961 is about 952.5163063505.

The spelling of 864205961 in words is "eight hundred sixty-four million, two hundred five thousand, nine hundred sixty-one".