11161210261 has 4 divisors (see below), whose sum is σ = 11748642400. Its totient is φ = 10573778124.

The previous prime is 11161210259. The next prime is 11161210267. The reversal of 11161210261 is 16201216111.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 16201216111 = 191 ⋅84823121.

It is a cyclic number.

It is not a de Polignac number, because 11161210261 - 2¹ = 11161210259 is a prime.

It is a super-2 number, since 2×11161210261² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11161210267) 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, 293716041 + ... + 293716078.

It is an arithmetic number, because the mean of its divisors is an integer number (2937160600).

Almost surely, 2^11161210261 is an apocalyptic number.

It is an amenable number.

11161210261 is a deficient number, since it is larger than the sum of its proper divisors (587432139).

11161210261 is an equidigital number, since it uses as much as digits as its factorization.

11161210261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 587432138.

The product of its (nonzero) digits is 144, while the sum is 22.

Adding to 11161210261 its reverse (16201216111), we get a palindrome (27362426372).

The spelling of 11161210261 in words is "eleven billion, one hundred sixty-one million, two hundred ten thousand, two hundred sixty-one".