261616293 has 6 divisors (see below), whose sum is σ = 377890214. Its totient is φ = 174410856.

The previous prime is 261616273. The next prime is 261616379. The reversal of 261616293 is 392616162.

It is a happy number.

261616293 is a `hidden beast` number, since 2 + 616 + 16 + 29 + 3 = 666.

It can be written as a sum of positive squares in only one way, i.e., 153809604 + 107806689 = 12402^2 + 10383^2 .

It is not a de Polignac number, because 261616293 - 2⁵ = 261616261 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 (261616253) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 14534230 + ... + 14534247.

Almost surely, 2^261616293 is an apocalyptic number.

It is an amenable number.

261616293 is a deficient number, since it is larger than the sum of its proper divisors (116273921).

261616293 is a wasteful number, since it uses less digits than its factorization.

261616293 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29068483 (or 29068480 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 261616293 is about 16174.5569645663. The cubic root of 261616293 is about 639.5702624549.

The spelling of 261616293 in words is "two hundred sixty-one million, six hundred sixteen thousand, two hundred ninety-three".