863953021 has 2 divisors, whose sum is σ = 863953022. Its totient is φ = 863953020.

The previous prime is 863953019. The next prime is 863953037. The reversal of 863953021 is 120359368.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 863536996 + 416025 = 29386^2 + 645^2 .

It is a cyclic number.

It is not a de Polignac number, because 863953021 - 2¹ = 863953019 is a prime.

Together with 863953019, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (863953421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 431976510 + 431976511.

It is an arithmetic number, because the mean of its divisors is an integer number (431976511).

Almost surely, 2^863953021 is an apocalyptic number.

It is an amenable number.

863953021 is a deficient number, since it is larger than the sum of its proper divisors (1).

863953021 is an equidigital number, since it uses as much as digits as its factorization.

863953021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 38880, while the sum is 37.

The square root of 863953021 is about 29393.0777735167. The cubic root of 863953021 is about 952.4233682490.

The spelling of 863953021 in words is "eight hundred sixty-three million, nine hundred fifty-three thousand, twenty-one".