261116623 has 4 divisors (see below), whose sum is σ = 261299520. Its totient is φ = 260933728.

The previous prime is 261116593. The next prime is 261116633. The reversal of 261116623 is 326611162.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 326611162 = 2 ⋅163305581.

It is a cyclic number.

It is not a de Polignac number, because 261116623 - 2²¹ = 259019471 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 261116591 and 261116600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261116633) 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, 89290 + ... + 92167.

It is an arithmetic number, because the mean of its divisors is an integer number (65324880).

Almost surely, 2^261116623 is an apocalyptic number.

261116623 is a deficient number, since it is larger than the sum of its proper divisors (182897).

261116623 is a wasteful number, since it uses less digits than its factorization.

261116623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 182896.

The product of its digits is 2592, while the sum is 28.

The square root of 261116623 is about 16159.1034095336. The cubic root of 261116623 is about 639.1628238346.

Adding to 261116623 its reverse (326611162), we get a palindrome (587727785).

The spelling of 261116623 in words is "two hundred sixty-one million, one hundred sixteen thousand, six hundred twenty-three".