261616208 has 40 divisors (see below), whose sum is σ = 580052160. Its totient is φ = 111974400.

The previous prime is 261616169. The next prime is 261616217. The reversal of 261616208 is 802616162.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 162608 + ... + 164208.

It is an arithmetic number, because the mean of its divisors is an integer number (14501304).

Almost surely, 2^261616208 is an apocalyptic number.

261616208 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

261616208 is an abundant number, since it is smaller than the sum of its proper divisors (318435952).

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

261616208 is a wasteful number, since it uses less digits than its factorization.

261616208 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3075 (or 3069 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 261616208 is about 16174.5543369825. The cubic root of 261616208 is about 639.5701931887.

The spelling of 261616208 in words is "two hundred sixty-one million, six hundred sixteen thousand, two hundred eight".