489656861 has 2 divisors, whose sum is σ = 489656862. Its totient is φ = 489656860.

The previous prime is 489656833. The next prime is 489656863. The reversal of 489656861 is 168656984.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 309936025 + 179720836 = 17605^2 + 13406^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-489656861 is a prime.

Together with 489656863, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (489656863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 244828430 + 244828431.

It is an arithmetic number, because the mean of its divisors is an integer number (244828431).

Almost surely, 2^489656861 is an apocalyptic number.

It is an amenable number.

489656861 is a deficient number, since it is larger than the sum of its proper divisors (1).

489656861 is an equidigital number, since it uses as much as digits as its factorization.

489656861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2488320, while the sum is 53.

The square root of 489656861 is about 22128.1915438203. The cubic root of 489656861 is about 788.1894449691.

The spelling of 489656861 in words is "four hundred eighty-nine million, six hundred fifty-six thousand, eight hundred sixty-one".