261234309 has 12 divisors (see below), whose sum is σ = 398184224. Its totient is φ = 149234424.

The previous prime is 261234271. The next prime is 261234317. The reversal of 261234309 is 903432162.

261234309 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 261234309 - 2¹² = 261230213 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 (261234109) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 72304 + ... + 75830.

Almost surely, 2^261234309 is an apocalyptic number.

It is an amenable number.

261234309 is a deficient number, since it is larger than the sum of its proper divisors (136949915).

261234309 is an frugal number, since it uses more digits than its factorization.

261234309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7064 (or 3537 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 30.

The square root of 261234309 is about 16162.7444761092. The cubic root of 261234309 is about 639.2588335759.

The spelling of 261234309 in words is "two hundred sixty-one million, two hundred thirty-four thousand, three hundred nine".