201143521 has 2 divisors, whose sum is σ = 201143522. Its totient is φ = 201143520.

The previous prime is 201143491. The next prime is 201143539. The reversal of 201143521 is 125341102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 120143521 + 81000000 = 10961^2 + 9000^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-201143521 is a prime.

It is not a weakly prime, because it can be changed into another prime (201143561) 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 as a sum of consecutive naturals, namely, 100571760 + 100571761.

It is an arithmetic number, because the mean of its divisors is an integer number (100571761).

Almost surely, 2^201143521 is an apocalyptic number.

It is an amenable number.

201143521 is a deficient number, since it is larger than the sum of its proper divisors (1).

201143521 is an equidigital number, since it uses as much as digits as its factorization.

201143521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 201143521 is about 14182.5075709481. The cubic root of 201143521 is about 585.9159887252.

Adding to 201143521 its reverse (125341102), we get a palindrome (326484623).

The spelling of 201143521 in words is "two hundred one million, one hundred forty-three thousand, five hundred twenty-one".