261225331 has 4 divisors (see below), whose sum is σ = 261308464. Its totient is φ = 261142200.

The previous prime is 261225311. The next prime is 261225343. The reversal of 261225331 is 133522162.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 261225331 - 2⁷ = 261225203 is a prime.

It is a super-2 number, since 2×261225331² = 136477347112119122, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 261225296 and 261225305.

It is not an unprimeable number, because it can be changed into a prime (261225311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36660 + ... + 43201.

It is an arithmetic number, because the mean of its divisors is an integer number (65327116).

Almost surely, 2^261225331 is an apocalyptic number.

261225331 is a deficient number, since it is larger than the sum of its proper divisors (83133).

261225331 is an equidigital number, since it uses as much as digits as its factorization.

261225331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83132.

The product of its digits is 2160, while the sum is 25.

The square root of 261225331 is about 16162.4667362380. The cubic root of 261225331 is about 639.2515102249.

Adding to 261225331 its reverse (133522162), we get a palindrome (394747493).

The spelling of 261225331 in words is "two hundred sixty-one million, two hundred twenty-five thousand, three hundred thirty-one".