287516561 has 2 divisors, whose sum is σ = 287516562. Its totient is φ = 287516560.

The previous prime is 287516519. The next prime is 287516609. The reversal of 287516561 is 165615782.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 241615936 + 45900625 = 15544^2 + 6775^2 .

It is a cyclic number.

It is not a de Polignac number, because 287516561 - 2¹⁴ = 287500177 is a prime.

It is a super-3 number, since 3×287516561³ (a number of 26 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (287546561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 143758280 + 143758281.

It is an arithmetic number, because the mean of its divisors is an integer number (143758281).

Almost surely, 2^287516561 is an apocalyptic number.

It is an amenable number.

287516561 is a deficient number, since it is larger than the sum of its proper divisors (1).

287516561 is an equidigital number, since it uses as much as digits as its factorization.

287516561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 100800, while the sum is 41.

The square root of 287516561 is about 16956.3133080278. The cubic root of 287516561 is about 660.0157334786.

The spelling of 287516561 in words is "two hundred eighty-seven million, five hundred sixteen thousand, five hundred sixty-one".