261688606 has 8 divisors (see below), whose sum is σ = 397501920. Its totient is φ = 129187968.

The previous prime is 261688601. The next prime is 261688619. The reversal of 261688606 is 606886162.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261688601) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 827971 + ... + 828286.

It is an arithmetic number, because the mean of its divisors is an integer number (49687740).

Almost surely, 2^261688606 is an apocalyptic number.

261688606 is a deficient number, since it is larger than the sum of its proper divisors (135813314).

261688606 is a wasteful number, since it uses less digits than its factorization.

261688606 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1656338.

The product of its (nonzero) digits is 165888, while the sum is 43.

The square root of 261688606 is about 16176.7922036478. The cubic root of 261688606 is about 639.6291846055.

The spelling of 261688606 in words is "two hundred sixty-one million, six hundred eighty-eight thousand, six hundred six".