261241121 has 2 divisors, whose sum is σ = 261241122. Its totient is φ = 261241120.

The previous prime is 261241103. The next prime is 261241147. The reversal of 261241121 is 121142162.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 245360896 + 15880225 = 15664^2 + 3985^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261241121 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 261241093 and 261241102.

It is not a weakly prime, because it can be changed into another prime (261244121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130620560 + 130620561.

It is an arithmetic number, because the mean of its divisors is an integer number (130620561).

Almost surely, 2^261241121 is an apocalyptic number.

It is an amenable number.

261241121 is a deficient number, since it is larger than the sum of its proper divisors (1).

261241121 is an equidigital number, since it uses as much as digits as its factorization.

261241121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 192, while the sum is 20.

The square root of 261241121 is about 16162.9552062734. The cubic root of 261241121 is about 639.2643900095.

Adding to 261241121 its reverse (121142162), we get a palindrome (382383283).

The spelling of 261241121 in words is "two hundred sixty-one million, two hundred forty-one thousand, one hundred twenty-one".