261242417 has 12 divisors (see below), whose sum is σ = 280882896. Its totient is φ = 242890560.

The previous prime is 261242369. The next prime is 261242431. The reversal of 261242417 is 714242162.

It is not a de Polignac number, because 261242417 - 2¹² = 261238321 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 261242417.

It is not an unprimeable number, because it can be changed into a prime (261242477) 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, 18542 + ... + 29432.

It is an arithmetic number, because the mean of its divisors is an integer number (23406908).

Almost surely, 2^261242417 is an apocalyptic number.

It is an amenable number.

261242417 is a deficient number, since it is larger than the sum of its proper divisors (19640479).

261242417 is a wasteful number, since it uses less digits than its factorization.

261242417 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11008 (or 10991 counting only the distinct ones).

The product of its digits is 5376, while the sum is 29.

The square root of 261242417 is about 16162.9952979019. The cubic root of 261242417 is about 639.2654471240.

Adding to 261242417 its reverse (714242162), we get a palindrome (975484579).

The spelling of 261242417 in words is "two hundred sixty-one million, two hundred forty-two thousand, four hundred seventeen".