871644457 has 2 divisors, whose sum is σ = 871644458. Its totient is φ = 871644456.

The previous prime is 871644407. The next prime is 871644463. The reversal of 871644457 is 754446178.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 501043456 + 370601001 = 22384^2 + 19251^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-871644457 is a prime.

It is not a weakly prime, because it can be changed into another prime (871644407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 435822228 + 435822229.

It is an arithmetic number, because the mean of its divisors is an integer number (435822229).

Almost surely, 2^871644457 is an apocalyptic number.

It is an amenable number.

871644457 is a deficient number, since it is larger than the sum of its proper divisors (1).

871644457 is an equidigital number, since it uses as much as digits as its factorization.

871644457 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 752640, while the sum is 46.

The square root of 871644457 is about 29523.6254040726. The cubic root of 871644457 is about 955.2413731598.

The spelling of 871644457 in words is "eight hundred seventy-one million, six hundred forty-four thousand, four hundred fifty-seven".