261487260 has 72 divisors (see below), whose sum is σ = 795478320. Its totient is φ = 69527808.

The previous prime is 261487231. The next prime is 261487301. The reversal of 261487260 is 62784162.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 66304 + ... + 70136.

It is an arithmetic number, because the mean of its divisors is an integer number (11048310).

Almost surely, 2^261487260 is an apocalyptic number.

261487260 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 261487260, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (397739160).

261487260 is an abundant number, since it is smaller than the sum of its proper divisors (533991060).

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

261487260 is a wasteful number, since it uses less digits than its factorization.

261487260 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4227 (or 4222 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 261487260 is about 16170.5677080305. The cubic root of 261487260 is about 639.4650966794.

The spelling of 261487260 in words is "two hundred sixty-one million, four hundred eighty-seven thousand, two hundred sixty".