861541823 has 2 divisors, whose sum is σ = 861541824. Its totient is φ = 861541822.

The previous prime is 861541789. The next prime is 861541853. The reversal of 861541823 is 328145168.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 861541823 - 2¹² = 861537727 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (861541853) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430770911 + 430770912.

It is an arithmetic number, because the mean of its divisors is an integer number (430770912).

Almost surely, 2^861541823 is an apocalyptic number.

861541823 is a deficient number, since it is larger than the sum of its proper divisors (1).

861541823 is an equidigital number, since it uses as much as digits as its factorization.

861541823 is an evil number, because the sum of its binary digits is even.

The product of its digits is 46080, while the sum is 38.

The square root of 861541823 is about 29352.0326894067. The cubic root of 861541823 is about 951.5365063509.

The spelling of 861541823 in words is "eight hundred sixty-one million, five hundred forty-one thousand, eight hundred twenty-three".