857214521 has 2 divisors, whose sum is σ = 857214522. Its totient is φ = 857214520.

The previous prime is 857214487. The next prime is 857214539. The reversal of 857214521 is 125412758.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 598487296 + 258727225 = 24464^2 + 16085^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-857214521 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (857214581) 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, 428607260 + 428607261.

It is an arithmetic number, because the mean of its divisors is an integer number (428607261).

Almost surely, 2^857214521 is an apocalyptic number.

It is an amenable number.

857214521 is a deficient number, since it is larger than the sum of its proper divisors (1).

857214521 is an equidigital number, since it uses as much as digits as its factorization.

857214521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 22400, while the sum is 35.

The square root of 857214521 is about 29278.2260562350. The cubic root of 857214521 is about 949.9407242794.

The spelling of 857214521 in words is "eight hundred fifty-seven million, two hundred fourteen thousand, five hundred twenty-one".