261804312 has 336 divisors, whose sum is σ = 941991120. Its totient is φ = 66718080.

The previous prime is 261804289. The next prime is 261804313. The reversal of 261804312 is 213408162.

261804312 is a `hidden beast` number, since 2 + 618 + 0 + 43 + 1 + 2 = 666.

261804312 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-3 number, since 3×261804312³ (a number of 26 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261804313) by changing a digit.

It is a polite number, since it can be written in 83 ways as a sum of consecutive naturals, for example, 4939678 + ... + 4939730.

It is an arithmetic number, because the mean of its divisors is an integer number (2803545).

Almost surely, 2^261804312 is an apocalyptic number.

261804312 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261804312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (470995560).

261804312 is an abundant number, since it is smaller than the sum of its proper divisors (680186808).

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

261804312 is a wasteful number, since it uses less digits than its factorization.

261804312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106 (or 76 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 261804312 is about 16180.3681045890. The cubic root of 261804312 is about 639.7234417081.

The spelling of 261804312 in words is "two hundred sixty-one million, eight hundred four thousand, three hundred twelve".