261088613 has 8 divisors (see below), whose sum is σ = 269198232. Its totient is φ = 253034496.

The previous prime is 261088609. The next prime is 261088627. The reversal of 261088613 is 316880162.

It can be written as a sum of positive squares in 4 ways, for example, as 99341089 + 161747524 = 9967^2 + 12718^2 .

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 261088613 - 2² = 261088609 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 (261088693) 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, 4220 + ... + 23237.

It is an arithmetic number, because the mean of its divisors is an integer number (33649779).

Almost surely, 2^261088613 is an apocalyptic number.

It is an amenable number.

261088613 is a deficient number, since it is larger than the sum of its proper divisors (8109619).

261088613 is a wasteful number, since it uses less digits than its factorization.

261088613 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27751.

The product of its (nonzero) digits is 13824, while the sum is 35.

The square root of 261088613 is about 16158.2366921642. The cubic root of 261088613 is about 639.1399686692.

The spelling of 261088613 in words is "two hundred sixty-one million, eighty-eight thousand, six hundred thirteen".