201511123441 has 4 divisors (see below), whose sum is σ = 208459782900. Its totient is φ = 194562463984.

The previous prime is 201511123391. The next prime is 201511123453. The reversal of 201511123441 is 144321115102.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 33182265600 + 168328857841 = 182160^2 + 410279^2 .

It is a cyclic number.

It is not a de Polignac number, because 201511123441 - 2¹⁹ = 201510599153 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (201511123241) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3474329686 + ... + 3474329743.

It is an arithmetic number, because the mean of its divisors is an integer number (52114945725).

Almost surely, 2^201511123441 is an apocalyptic number.

It is an amenable number.

201511123441 is a deficient number, since it is larger than the sum of its proper divisors (6948659459).

201511123441 is an equidigital number, since it uses as much as digits as its factorization.

201511123441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6948659458.

The product of its (nonzero) digits is 960, while the sum is 25.

Adding to 201511123441 its reverse (144321115102), we get a palindrome (345832238543).

The spelling of 201511123441 in words is "two hundred one billion, five hundred eleven million, one hundred twenty-three thousand, four hundred forty-one".