261032320 has 64 divisors (see below), whose sum is σ = 627312240. Its totient is φ = 103864320.

The previous prime is 261032309. The next prime is 261032323. The reversal of 261032320 is 23230162.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261032323) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 134074 + ... + 136006.

Almost surely, 2^261032320 is an apocalyptic number.

261032320 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 261032320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (313656120).

261032320 is an abundant number, since it is smaller than the sum of its proper divisors (366279920).

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

261032320 is a wasteful number, since it uses less digits than its factorization.

261032320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2163 (or 2151 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 19.

The square root of 261032320 is about 16156.4946693273. The cubic root of 261032320 is about 639.0940306356.

Adding to 261032320 its reverse (23230162), we get a palindrome (284262482).

The spelling of 261032320 in words is "two hundred sixty-one million, thirty-two thousand, three hundred twenty".