200021987 has 8 divisors (see below), whose sum is σ = 229690560. Its totient is φ = 172267560.

The previous prime is 200021953. The next prime is 200022029. The reversal of 200021987 is 789120002.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 200021987 - 2¹⁶ = 199956451 is a prime.

It is not an unprimeable number, because it can be changed into a prime (200021587) 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 in 7 ways as a sum of consecutive naturals, for example, 478313 + ... + 478730.

It is an arithmetic number, because the mean of its divisors is an integer number (28711320).

Almost surely, 2^200021987 is an apocalyptic number.

200021987 is a deficient number, since it is larger than the sum of its proper divisors (29668573).

200021987 is a wasteful number, since it uses less digits than its factorization.

200021987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 957073.

The product of its (nonzero) digits is 2016, while the sum is 29.

The square root of 200021987 is about 14142.9129602073. The cubic root of 200021987 is about 584.8249769833.

Adding to 200021987 its reverse (789120002), we get a palindrome (989141989).

The spelling of 200021987 in words is "two hundred million, twenty-one thousand, nine hundred eighty-seven".