26161616261 has 4 divisors (see below), whose sum is σ = 28539945024. Its totient is φ = 23783287500.

The previous prime is 26161616207. The next prime is 26161616267. The reversal of 26161616261 is 16261616162.

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.

It is a cyclic number.

It is not a de Polignac number, because 26161616261 - 2³⁰ = 25087874437 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (26161616267) 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 in 3 ways as a sum of consecutive naturals, for example, 1189164365 + ... + 1189164386.

It is an arithmetic number, because the mean of its divisors is an integer number (7134986256).

Almost surely, 2^26161616261 is an apocalyptic number.

It is an amenable number.

26161616261 is a deficient number, since it is larger than the sum of its proper divisors (2378328763).

26161616261 is a wasteful number, since it uses less digits than its factorization.

26161616261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2378328762.

The product of its digits is 31104, while the sum is 38.

Subtracting from 26161616261 its reverse (16261616162), we obtain a palindrome (9900000099).

The spelling of 26161616261 in words is "twenty-six billion, one hundred sixty-one million, six hundred sixteen thousand, two hundred sixty-one".