864138189091 has 2 divisors, whose sum is σ = 864138189092. Its totient is φ = 864138189090.

The previous prime is 864138189059. The next prime is 864138189113. The reversal of 864138189091 is 190981831468.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 864138189091 - 2⁵ = 864138189059 is a prime.

It is not a weakly prime, because it can be changed into another prime (864138189011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 432069094545 + 432069094546.

It is an arithmetic number, because the mean of its divisors is an integer number (432069094546).

Almost surely, 2^864138189091 is an apocalyptic number.

864138189091 is a deficient number, since it is larger than the sum of its proper divisors (1).

864138189091 is an equidigital number, since it uses as much as digits as its factorization.

864138189091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2985984, while the sum is 58.

The spelling of 864138189091 in words is "eight hundred sixty-four billion, one hundred thirty-eight million, one hundred eighty-nine thousand, ninety-one".