200811561 has 4 divisors (see below), whose sum is σ = 267748752. Its totient is φ = 133874372.

The previous prime is 200811557. The next prime is 200811587. The reversal of 200811561 is 165118002.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 200811561 - 2² = 200811557 is a prime.

It is not an unprimeable number, because it can be changed into a prime (200811461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33468591 + ... + 33468596.

It is an arithmetic number, because the mean of its divisors is an integer number (66937188).

Almost surely, 2^200811561 is an apocalyptic number.

It is an amenable number.

200811561 is a deficient number, since it is larger than the sum of its proper divisors (66937191).

200811561 is an equidigital number, since it uses as much as digits as its factorization.

200811561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66937190.

The product of its (nonzero) digits is 480, while the sum is 24.

The square root of 200811561 is about 14170.7995892963. The cubic root of 200811561 is about 585.5934863849.

Adding to 200811561 its reverse (165118002), we get a palindrome (365929563).

The spelling of 200811561 in words is "two hundred million, eight hundred eleven thousand, five hundred sixty-one".