866957398999 has 2 divisors, whose sum is σ = 866957399000. Its totient is φ = 866957398998.

The previous prime is 866957398943. The next prime is 866957399017. The reversal of 866957398999 is 999893759668.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 866957398999 - 2¹⁹ = 866956874711 is a prime.

It is a super-2 number, since 2×866957398999² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (866957398499) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 433478699499 + 433478699500.

It is an arithmetic number, because the mean of its divisors is an integer number (433478699500).

Almost surely, 2^866957398999 is an apocalyptic number.

866957398999 is a deficient number, since it is larger than the sum of its proper divisors (1).

866957398999 is an equidigital number, since it uses as much as digits as its factorization.

866957398999 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 14285134080, while the sum is 88.

The spelling of 866957398999 in words is "eight hundred sixty-six billion, nine hundred fifty-seven million, three hundred ninety-eight thousand, nine hundred ninety-nine".