864643081 has 2 divisors, whose sum is σ = 864643082. Its totient is φ = 864643080.

The previous prime is 864643061. The next prime is 864643093. The reversal of 864643081 is 180346468.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 554178681 + 310464400 = 23541^2 + 17620^2 .

It is a cyclic number.

It is not a de Polignac number, because 864643081 - 2⁵ = 864643049 is a prime.

It is a super-2 number, since 2×864643081² = 1495215315042345122, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (864643061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 432321540 + 432321541.

It is an arithmetic number, because the mean of its divisors is an integer number (432321541).

Almost surely, 2^864643081 is an apocalyptic number.

It is an amenable number.

864643081 is a deficient number, since it is larger than the sum of its proper divisors (1).

864643081 is an equidigital number, since it uses as much as digits as its factorization.

864643081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 110592, while the sum is 40.

The square root of 864643081 is about 29404.8139086103. The cubic root of 864643081 is about 952.6768752298.

The spelling of 864643081 in words is "eight hundred sixty-four million, six hundred forty-three thousand, eighty-one".