872787661 has 2 divisors, whose sum is σ = 872787662. Its totient is φ = 872787660.

The previous prime is 872787607. The next prime is 872787673. The reversal of 872787661 is 166787278.

872787661 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., 690375625 + 182412036 = 26275^2 + 13506^2 .

It is a cyclic number.

It is not a de Polignac number, because 872787661 - 2¹⁵ = 872754893 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 872787599 and 872787608.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (872787691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 436393830 + 436393831.

It is an arithmetic number, because the mean of its divisors is an integer number (436393831).

Almost surely, 2^872787661 is an apocalyptic number.

It is an amenable number.

872787661 is a deficient number, since it is larger than the sum of its proper divisors (1).

872787661 is an equidigital number, since it uses as much as digits as its factorization.

872787661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1580544, while the sum is 52.

The square root of 872787661 is about 29542.9798937074. The cubic root of 872787661 is about 955.6588058558.

The spelling of 872787661 in words is "eight hundred seventy-two million, seven hundred eighty-seven thousand, six hundred sixty-one".