857221451 has 2 divisors, whose sum is σ = 857221452. Its totient is φ = 857221450.

The previous prime is 857221369. The next prime is 857221457. The reversal of 857221451 is 154122758.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-857221451 is a prime.

It is equal to p_43932914 and since 857221451 and 43932914 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (857221457) 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, 428610725 + 428610726.

It is an arithmetic number, because the mean of its divisors is an integer number (428610726).

Almost surely, 2^857221451 is an apocalyptic number.

857221451 is a deficient number, since it is larger than the sum of its proper divisors (1).

857221451 is an equidigital number, since it uses as much as digits as its factorization.

857221451 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 857221451 is about 29278.3444033299. The cubic root of 857221451 is about 949.9432841487.

The spelling of 857221451 in words is "eight hundred fifty-seven million, two hundred twenty-one thousand, four hundred fifty-one".