261423305 has 16 divisors (see below), whose sum is σ = 368553024. Its totient is φ = 175500480.

The previous prime is 261423289. The next prime is 261423307. The reversal of 261423305 is 503324162.

It is not a de Polignac number, because 261423305 - 2⁴ = 261423289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261423307) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 182099 + ... + 183528.

It is an arithmetic number, because the mean of its divisors is an integer number (23034564).

Almost surely, 2^261423305 is an apocalyptic number.

It is an amenable number.

261423305 is a deficient number, since it is larger than the sum of its proper divisors (107129719).

261423305 is a wasteful number, since it uses less digits than its factorization.

261423305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 365656.

The product of its (nonzero) digits is 4320, while the sum is 26.

The square root of 261423305 is about 16168.5900745860. The cubic root of 261423305 is about 639.4129586072.

Adding to 261423305 its reverse (503324162), we get a palindrome (764747467).

The spelling of 261423305 in words is "two hundred sixty-one million, four hundred twenty-three thousand, three hundred five".