261465560 has 64 divisors (see below), whose sum is σ = 601318080. Its totient is φ = 102297600.

The previous prime is 261465553. The next prime is 261465571. The reversal of 261465560 is 65564162.

It is a super-2 number, since 2×261465560² = 136728478132227200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 261465560.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 440624 + ... + 441216.

It is an arithmetic number, because the mean of its divisors is an integer number (9395595).

Almost surely, 2^261465560 is an apocalyptic number.

261465560 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 261465560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (300659040).

261465560 is an abundant number, since it is smaller than the sum of its proper divisors (339852520).

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

261465560 is a wasteful number, since it uses less digits than its factorization.

261465560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 828 (or 824 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 35.

The square root of 261465560 is about 16169.8967219955. The cubic root of 261465560 is about 639.4474071287.

The spelling of 261465560 in words is "two hundred sixty-one million, four hundred sixty-five thousand, five hundred sixty".