261223535 has 16 divisors (see below), whose sum is σ = 327533760. Its totient is φ = 199626240.

The previous prime is 261223511. The next prime is 261223541. The reversal of 261223535 is 535322162.

261223535 is nontrivially palindromic in base 4.

It is not a de Polignac number, because 261223535 - 2⁸ = 261223279 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 261223498 and 261223507.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 155681 + ... + 157349.

It is an arithmetic number, because the mean of its divisors is an integer number (20470860).

Almost surely, 2^261223535 is an apocalyptic number.

261223535 is a deficient number, since it is larger than the sum of its proper divisors (66310225).

261223535 is a wasteful number, since it uses less digits than its factorization.

261223535 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3058.

The product of its digits is 10800, while the sum is 29.

The square root of 261223535 is about 16162.4111753166. The cubic root of 261223535 is about 639.2500452083.

Adding to 261223535 its reverse (535322162), we get a palindrome (796545697).

The spelling of 261223535 in words is "two hundred sixty-one million, two hundred twenty-three thousand, five hundred thirty-five".