261305400 has 96 divisors (see below), whose sum is σ = 812827440. Its totient is φ = 69442560.

The previous prime is 261305393. The next prime is 261305411. The reversal of 261305400 is 4503162.

It is a happy number.

261305400 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 237652 + ... + 238748.

Almost surely, 2^261305400 is an apocalyptic number.

261305400 is a gapful number since it is divisible by the number (20) 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 261305400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (406413720).

261305400 is an abundant number, since it is smaller than the sum of its proper divisors (551522040).

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

261305400 is a wasteful number, since it uses less digits than its factorization.

261305400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1513 (or 1504 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 21.

The square root of 261305400 is about 16164.9435507830. The cubic root of 261305400 is about 639.3168165518.

Adding to 261305400 its reverse (4503162), we get a palindrome (265808562).

The spelling of 261305400 in words is "two hundred sixty-one million, three hundred five thousand, four hundred".