261365632 has 128 divisors (see below), whose sum is σ = 606981600. Its totient is φ = 110960640.

The previous prime is 261365617. The next prime is 261365639. The reversal of 261365632 is 236563162.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261365639) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1510698 + ... + 1510870.

Almost surely, 2^261365632 is an apocalyptic number.

261365632 is a gapful number since it is divisible by the number (22) 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 261365632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (303490800).

261365632 is an abundant number, since it is smaller than the sum of its proper divisors (345615968).

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

261365632 is a wasteful number, since it uses less digits than its factorization.

261365632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 264 (or 252 counting only the distinct ones).

The product of its digits is 38880, while the sum is 34.

The square root of 261365632 is about 16166.8064873679. The cubic root of 261365632 is about 639.3659345215.

It can be divided in two parts, 26136 and 5632, that multiplied together give a cube (147197952 = 528³).

The spelling of 261365632 in words is "two hundred sixty-one million, three hundred sixty-five thousand, six hundred thirty-two".