201003561 has 24 divisors (see below), whose sum is σ = 318034080. Its totient is φ = 121320000.

The previous prime is 201003559. The next prime is 201003581. The reversal of 201003561 is 165300102.

201003561 is a `hidden beast` number, since 2 + 0 + 100 + 3 + 561 = 666.

It is not a de Polignac number, because 201003561 - 2¹ = 201003559 is a prime.

It is not an unprimeable number, because it can be changed into a prime (201003511) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 20805 + ... + 28893.

It is an arithmetic number, because the mean of its divisors is an integer number (13251420).

Almost surely, 2^201003561 is an apocalyptic number.

It is an amenable number.

201003561 is a deficient number, since it is larger than the sum of its proper divisors (117030519).

201003561 is a wasteful number, since it uses less digits than its factorization.

201003561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8357 (or 8354 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 18.

The square root of 201003561 is about 14177.5724649885. The cubic root of 201003561 is about 585.7800595323.

Adding to 201003561 its reverse (165300102), we get a palindrome (366303663).

The spelling of 201003561 in words is "two hundred one million, three thousand, five hundred sixty-one".