261055080 has 288 divisors, whose sum is σ = 1006485480. Its totient is φ = 58291200.

The previous prime is 261055073. The next prime is 261055087. The reversal of 261055080 is 80550162.

261055080 is a `hidden beast` number, since 26 + 10 + 550 + 80 = 666.

It is an interprime number because it is at equal distance from previous prime (261055073) and next prime (261055087).

It can be written as a sum of positive squares in 4 ways, for example, as 139570596 + 121484484 = 11814^2 + 11022^2 .

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (261055087) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 566050 + ... + 566510.

Almost surely, 2^261055080 is an apocalyptic number.

261055080 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 261055080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (503242740).

261055080 is an abundant number, since it is smaller than the sum of its proper divisors (745430400).

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

261055080 is a wasteful number, since it uses less digits than its factorization.

261055080 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 513 (or 495 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 27.

The square root of 261055080 is about 16157.1990146807. The cubic root of 261055080 is about 639.1126047818.

The spelling of 261055080 in words is "two hundred sixty-one million, fifty-five thousand, eighty".