864521249 has 2 divisors, whose sum is σ = 864521250. Its totient is φ = 864521248.

The previous prime is 864521209. The next prime is 864521257. The reversal of 864521249 is 942125468.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 837813025 + 26708224 = 28945^2 + 5168^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-864521249 is a prime.

It is not a weakly prime, because it can be changed into another prime (864521209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 432260624 + 432260625.

It is an arithmetic number, because the mean of its divisors is an integer number (432260625).

Almost surely, 2^864521249 is an apocalyptic number.

It is an amenable number.

864521249 is a deficient number, since it is larger than the sum of its proper divisors (1).

864521249 is an equidigital number, since it uses as much as digits as its factorization.

864521249 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 138240, while the sum is 41.

The square root of 864521249 is about 29402.7422020464. The cubic root of 864521249 is about 952.6321276788.

The spelling of 864521249 in words is "eight hundred sixty-four million, five hundred twenty-one thousand, two hundred forty-nine".