261601308 has 72 divisors (see below), whose sum is σ = 673072400. Its totient is φ = 85660416.

The previous prime is 261601289. The next prime is 261601313. The reversal of 261601308 is 803106162.

261601308 is a `hidden beast` number, since 26 + 1 + 601 + 30 + 8 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 639408 + ... + 639816.

Almost surely, 2^261601308 is an apocalyptic number.

It is an amenable number.

261601308 is an abundant number, since it is smaller than the sum of its proper divisors (411471092).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261601308 is a wasteful number, since it uses less digits than its factorization.

261601308 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 691 (or 686 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 261601308 is about 16174.0937304073. The cubic root of 261601308 is about 639.5580510042.

The spelling of 261601308 in words is "two hundred sixty-one million, six hundred one thousand, three hundred eight".