261645160 has 64 divisors (see below), whose sum is σ = 674593920. Its totient is φ = 89468160.

The previous prime is 261645127. The next prime is 261645169. The reversal of 261645160 is 61546162.

261645160 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (261645169) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 128067 + ... + 130093.

It is an arithmetic number, because the mean of its divisors is an integer number (10540530).

Almost surely, 2^261645160 is an apocalyptic number.

261645160 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 261645160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (337296960).

261645160 is an abundant number, since it is smaller than the sum of its proper divisors (412948760).

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

261645160 is a wasteful number, since it uses less digits than its factorization.

261645160 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2506 (or 2502 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 261645160 is about 16175.4492982421. The cubic root of 261645160 is about 639.5937851944.

The spelling of 261645160 in words is "two hundred sixty-one million, six hundred forty-five thousand, one hundred sixty".