669887987 has 2 divisors, whose sum is σ = 669887988. Its totient is φ = 669887986.

The previous prime is 669887969. The next prime is 669888017. The reversal of 669887987 is 789788966.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 669887987 - 2¹⁰ = 669886963 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (669887957) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334943993 + 334943994.

It is an arithmetic number, because the mean of its divisors is an integer number (334943994).

Almost surely, 2^669887987 is an apocalyptic number.

669887987 is a deficient number, since it is larger than the sum of its proper divisors (1).

669887987 is an equidigital number, since it uses as much as digits as its factorization.

669887987 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 73156608, while the sum is 68.

The square root of 669887987 is about 25882.1944007845. The cubic root of 669887987 is about 874.9852457920.

It can be divided in two parts, 6698879 and 87, that added together give a palindrome (6698966).

The spelling of 669887987 in words is "six hundred sixty-nine million, eight hundred eighty-seven thousand, nine hundred eighty-seven".