872857858721 has 2 divisors, whose sum is σ = 872857858722. Its totient is φ = 872857858720.

The previous prime is 872857858711. The next prime is 872857858723. The reversal of 872857858721 is 127858758278.

872857858721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 871506267025 + 1351591696 = 933545^2 + 36764^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-872857858721 is a prime.

Together with 872857858723, 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 (872857858723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 436428929360 + 436428929361.

It is an arithmetic number, because the mean of its divisors is an integer number (436428929361).

Almost surely, 2^872857858721 is an apocalyptic number.

It is an amenable number.

872857858721 is a deficient number, since it is larger than the sum of its proper divisors (1).

872857858721 is an equidigital number, since it uses as much as digits as its factorization.

872857858721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 140492800, while the sum is 68.

The spelling of 872857858721 in words is "eight hundred seventy-two billion, eight hundred fifty-seven million, eight hundred fifty-eight thousand, seven hundred twenty-one".