261289152 has 168 divisors, whose sum is σ = 793827216. Its totient is φ = 85183488.

The previous prime is 261289151. The next prime is 261289157. The reversal of 261289152 is 251982162.

261289152 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (261289151) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 824098 + ... + 824414.

It is an arithmetic number, because the mean of its divisors is an integer number (4725162).

Almost surely, 2^261289152 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 261289152, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (396913608).

261289152 is an abundant number, since it is smaller than the sum of its proper divisors (532538064).

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

261289152 is an equidigital number, since it uses as much as digits as its factorization.

261289152 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 397 (or 375 counting only the distinct ones).

The product of its digits is 17280, while the sum is 36.

The square root of 261289152 is about 16164.4409739403. The cubic root of 261289152 is about 639.3035653459.

The spelling of 261289152 in words is "two hundred sixty-one million, two hundred eighty-nine thousand, one hundred fifty-two".