261451013610517 has 8 divisors (see below), whose sum is σ = 262576382700632. Its totient is φ = 260325979315200.

The previous prime is 261451013610431. The next prime is 261451013610559. The reversal of 261451013610517 is 715016310154162.

It can be written as a sum of positive squares in 4 ways, for example, as 138959443067236 + 122491570543281 = 11788106^2 + 11067591^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 261451013610517 - 2¹¹ = 261451013608469 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 (261451013610317) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 82133418 + ... + 85257259.

It is an arithmetic number, because the mean of its divisors is an integer number (32822047837579).

Almost surely, 2^{261451013610517} is an apocalyptic number.

It is an amenable number.

261451013610517 is a deficient number, since it is larger than the sum of its proper divisors (1125369090115).

261451013610517 is a wasteful number, since it uses less digits than its factorization.

261451013610517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167397399.

The product of its (nonzero) digits is 151200, while the sum is 43.

Adding to 261451013610517 its reverse (715016310154162), we get a palindrome (976467323764679).

The spelling of 261451013610517 in words is "two hundred sixty-one trillion, four hundred fifty-one billion, thirteen million, six hundred ten thousand, five hundred seventeen".