261388296 has 96 divisors (see below), whose sum is σ = 790695360. Its totient is φ = 80419392.

The previous prime is 261388279. The next prime is 261388319. The reversal of 261388296 is 692883162.

261388296 is a `hidden beast` number, since 2 + 613 + 8 + 8 + 29 + 6 = 666.

It is a nude number because it is divisible by every one of its digits.

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, 20101 + ... + 30443.

It is an arithmetic number, because the mean of its divisors is an integer number (8236410).

Almost surely, 2^261388296 is an apocalyptic number.

261388296 is a gapful number since it is divisible by the number (26) 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 261388296, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (395347680).

261388296 is an abundant number, since it is smaller than the sum of its proper divisors (529307064).

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

261388296 is a wasteful number, since it uses less digits than its factorization.

261388296 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10377 (or 10361 counting only the distinct ones).

The product of its digits is 248832, while the sum is 45.

The square root of 261388296 is about 16167.5074145646. The cubic root of 261388296 is about 639.3844145981.

It can be divided in two parts, 2613 and 88296, that added together give a palindrome (90909).

The spelling of 261388296 in words is "two hundred sixty-one million, three hundred eighty-eight thousand, two hundred ninety-six".