261684416 has 112 divisors (see below), whose sum is σ = 634959360. Its totient is φ = 104509440.

The previous prime is 261684407. The next prime is 261684431. The reversal of 261684416 is 614486162.

261684416 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (112).

It is a super-2 number, since 2×261684416² = 136957467154522112, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a zygodrome in base 2.

It is a self number, because there is not a number n which added to its sum of digits gives 261684416.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 604136 + ... + 604568.

It is an arithmetic number, because the mean of its divisors is an integer number (5669280).

Almost surely, 2^261684416 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261684416, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (317479680).

261684416 is an abundant number, since it is smaller than the sum of its proper divisors (373274944).

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

261684416 is a wasteful number, since it uses less digits than its factorization.

261684416 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 542 (or 532 counting only the distinct ones).

The product of its digits is 55296, while the sum is 38.

The square root of 261684416 is about 16176.6626966133. The cubic root of 261684416 is about 639.6257708018.

The spelling of 261684416 in words is "two hundred sixty-one million, six hundred eighty-four thousand, four hundred sixteen".