261510648 has 96 divisors (see below), whose sum is σ = 772099200. Its totient is φ = 73579968.

The previous prime is 261510647. The next prime is 261510703. The reversal of 261510648 is 846015162.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261510647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 77133 + ... + 80451.

It is an arithmetic number, because the mean of its divisors is an integer number (8042700).

Almost surely, 2^261510648 is an apocalyptic number.

261510648 is a gapful number since it is divisible by the number (28) 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 261510648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (386049600).

261510648 is an abundant number, since it is smaller than the sum of its proper divisors (510588552).

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

261510648 is a wasteful number, since it uses less digits than its factorization.

261510648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3409 (or 3398 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 33.

The square root of 261510648 is about 16171.2908575661. The cubic root of 261510648 is about 639.4841611695.

The spelling of 261510648 in words is "two hundred sixty-one million, five hundred ten thousand, six hundred forty-eight".