261934560 has 144 divisors (see below), whose sum is σ = 927094896. Its totient is φ = 69838848.

The previous prime is 261934559. The next prime is 261934567. The reversal of 261934560 is 65439162.

It is a happy number.

261934560 is a `hidden beast` number, since 2 + 6 + 1 + 93 + 4 + 560 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261934567) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 35512 + ... + 42248.

It is an arithmetic number, because the mean of its divisors is an integer number (6438159).

Almost surely, 2^261934560 is an apocalyptic number.

261934560 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 261934560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (463547448).

261934560 is an abundant number, since it is smaller than the sum of its proper divisors (665160336).

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

261934560 is an equidigital number, since it uses as much as digits as its factorization.

261934560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6767 (or 6747 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 36.

The square root of 261934560 is about 16184.3924816472. The cubic root of 261934560 is about 639.8295118798.

The spelling of 261934560 in words is "two hundred sixty-one million, nine hundred thirty-four thousand, five hundred sixty".