871557761 has 2 divisors, whose sum is σ = 871557762. Its totient is φ = 871557760.

The previous prime is 871557737. The next prime is 871557763. The reversal of 871557761 is 167755178.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 862890625 + 8667136 = 29375^2 + 2944^2 .

It is a cyclic number.

It is not a de Polignac number, because 871557761 - 2⁶ = 871557697 is a prime.

It is a super-2 number, since 2×871557761² = 1519225861518666242, which contains 22 as substring.

Together with 871557763, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (871557763) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 435778880 + 435778881.

It is an arithmetic number, because the mean of its divisors is an integer number (435778881).

Almost surely, 2^871557761 is an apocalyptic number.

It is an amenable number.

871557761 is a deficient number, since it is larger than the sum of its proper divisors (1).

871557761 is an equidigital number, since it uses as much as digits as its factorization.

871557761 is an evil number, because the sum of its binary digits is even.

The product of its digits is 411600, while the sum is 47.

The square root of 871557761 is about 29522.1571196957. The cubic root of 871557761 is about 955.2097018549.

The spelling of 871557761 in words is "eight hundred seventy-one million, five hundred fifty-seven thousand, seven hundred sixty-one".