261551104 has 44 divisors (see below), whose sum is σ = 526390144. Its totient is φ = 129890304.

The previous prime is 261551053. The next prime is 261551107. The reversal of 261551104 is 401155162.

It is a happy number.

261551104 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261551107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 166129 + ... + 167695.

Almost surely, 2^261551104 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 261551104, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (263195072).

261551104 is an abundant number, since it is smaller than the sum of its proper divisors (264839040).

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

261551104 is a wasteful number, since it uses less digits than its factorization.

261551104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1750 (or 1732 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 25.

The square root of 261551104 is about 16172.5416679012. The cubic root of 261551104 is about 639.5171357825.

The spelling of 261551104 in words is "two hundred sixty-one million, five hundred fifty-one thousand, one hundred four".