261431184 has 160 divisors (see below), whose sum is σ = 839311360. Its totient is φ = 68428800.

The previous prime is 261431173. The next prime is 261431189. The reversal of 261431184 is 481134162.

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (261431189) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 197244 + ... + 198564.

It is an arithmetic number, because the mean of its divisors is an integer number (5245696).

Almost surely, 2^261431184 is an apocalyptic number.

261431184 is a gapful number since it is divisible by the number (24) 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 261431184, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (419655680).

261431184 is an abundant number, since it is smaller than the sum of its proper divisors (577880176).

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

261431184 is a wasteful number, since it uses less digits than its factorization.

261431184 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1389 (or 1383 counting only the distinct ones).

The product of its digits is 4608, while the sum is 30.

The square root of 261431184 is about 16168.8337241744. The cubic root of 261431184 is about 639.4193822682.

The spelling of 261431184 in words is "two hundred sixty-one million, four hundred thirty-one thousand, one hundred eighty-four".