873661047521 has 2 divisors, whose sum is σ = 873661047522. Its totient is φ = 873661047520.

The previous prime is 873661047499. The next prime is 873661047529. The reversal of 873661047521 is 125740166378.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 650782637521 + 222878410000 = 806711^2 + 472100^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-873661047521 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 873661047521.

It is not a weakly prime, because it can be changed into another prime (873661047529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 436830523760 + 436830523761.

It is an arithmetic number, because the mean of its divisors is an integer number (436830523761).

Almost surely, 2^873661047521 is an apocalyptic number.

It is an amenable number.

873661047521 is a deficient number, since it is larger than the sum of its proper divisors (1).

873661047521 is an equidigital number, since it uses as much as digits as its factorization.

873661047521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1693440, while the sum is 50.

The spelling of 873661047521 in words is "eight hundred seventy-three billion, six hundred sixty-one million, forty-seven thousand, five hundred twenty-one".