987646789 has 2 divisors, whose sum is σ = 987646790. Its totient is φ = 987646788.

The previous prime is 987646787. The next prime is 987646801.

987646789 is nontrivially palindromic in base 10.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 545596164 + 442050625 = 23358^2 + 21025^2 .

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 987646789 - 2¹ = 987646787 is a prime.

Together with 987646787, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 987646789.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (987646783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 493823394 + 493823395.

It is an arithmetic number, because the mean of its divisors is an integer number (493823395).

Almost surely, 2^987646789 is an apocalyptic number.

It is an amenable number.

987646789 is a deficient number, since it is larger than the sum of its proper divisors (1).

987646789 is an equidigital number, since it uses as much as digits as its factorization.

987646789 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36578304, while the sum is 64.

The square root of 987646789 is about 31426.8482193172. The cubic root of 987646789 is about 995.8651899093.

It can be divided in two parts, 9876 and 46789, that added together give a palindrome (56665).

The spelling of 987646789 in words is "nine hundred eighty-seven million, six hundred forty-six thousand, seven hundred eighty-nine".