200121805 has 16 divisors (see below), whose sum is σ = 263007360. Its totient is φ = 145274688.

The previous prime is 200121769. The next prime is 200121809. The reversal of 200121805 is 508121002.

It is not a de Polignac number, because 200121805 - 2²³ = 191733197 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (200121809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22257 + ... + 29926.

It is an arithmetic number, because the mean of its divisors is an integer number (16437960).

Almost surely, 2^200121805 is an apocalyptic number.

It is an amenable number.

200121805 is a deficient number, since it is larger than the sum of its proper divisors (62885555).

200121805 is a wasteful number, since it uses less digits than its factorization.

200121805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52260.

The product of its (nonzero) digits is 160, while the sum is 19.

The square root of 200121805 is about 14146.4414253197. The cubic root of 200121805 is about 584.9222435431.

Adding to 200121805 its reverse (508121002), we get a palindrome (708242807).

The spelling of 200121805 in words is "two hundred million, one hundred twenty-one thousand, eight hundred five".