261655296 has 216 divisors, whose sum is σ = 859829040. Its totient is φ = 70189056.

The previous prime is 261655271. The next prime is 261655319. The reversal of 261655296 is 692556162.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 639540 + ... + 639948.

It is an arithmetic number, because the mean of its divisors is an integer number (3980690).

Almost surely, 2^261655296 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 261655296, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (429914520).

261655296 is an abundant number, since it is smaller than the sum of its proper divisors (598173744).

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

261655296 is a wasteful number, since it uses less digits than its factorization.

261655296 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 459 (or 438 counting only the distinct ones).

The product of its digits is 194400, while the sum is 42.

The square root of 261655296 is about 16175.7626095341. The cubic root of 261655296 is about 639.6020442668.

The spelling of 261655296 in words is "two hundred sixty-one million, six hundred fifty-five thousand, two hundred ninety-six".