261981832 has 48 divisors (see below), whose sum is σ = 605042460. Its totient is φ = 105670656.

The previous prime is 261981817. The next prime is 261981833. The reversal of 261981832 is 238189162.

261981832 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 249829636 + 12152196 = 15806^2 + 3486^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261981833) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12993 + ... + 26320.

Almost surely, 2^261981832 is an apocalyptic number.

It is an amenable number.

261981832 is an abundant number, since it is smaller than the sum of its proper divisors (343060628).

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

261981832 is a wasteful number, since it uses less digits than its factorization.

261981832 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39350 (or 39339 counting only the distinct ones).

The product of its digits is 41472, while the sum is 40.

The square root of 261981832 is about 16185.8528351150. The cubic root of 261981832 is about 639.8680001207.

The spelling of 261981832 in words is "two hundred sixty-one million, nine hundred eighty-one thousand, eight hundred thirty-two".