864358572221 has 2 divisors, whose sum is σ = 864358572222. Its totient is φ = 864358572220.

The previous prime is 864358572191. The next prime is 864358572263. The reversal of 864358572221 is 122275853468.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 528694768996 + 335663803225 = 727114^2 + 579365^2 .

It is a cyclic number.

It is not a de Polignac number, because 864358572221 - 2⁶ = 864358572157 is a prime.

It is a super-4 number, since 4×864358572221⁴ (a number of 49 digits) contains 4444 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (864358571221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 432179286110 + 432179286111.

It is an arithmetic number, because the mean of its divisors is an integer number (432179286111).

Almost surely, 2^864358572221 is an apocalyptic number.

It is an amenable number.

864358572221 is a deficient number, since it is larger than the sum of its proper divisors (1).

864358572221 is an equidigital number, since it uses as much as digits as its factorization.

864358572221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6451200, while the sum is 53.

The spelling of 864358572221 in words is "eight hundred sixty-four billion, three hundred fifty-eight million, five hundred seventy-two thousand, two hundred twenty-one".