261523080 has 320 divisors, whose sum is σ = 1083075840. Its totient is φ = 55116288.

The previous prime is 261523063. The next prime is 261523103. The reversal of 261523080 is 80325162.

261523080 is a `hidden beast` number, since 2 + 61 + 523 + 0 + 80 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 294397 + ... + 295283.

It is an arithmetic number, because the mean of its divisors is an integer number (3384612).

Almost surely, 2^261523080 is an apocalyptic number.

261523080 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 261523080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (541537920).

261523080 is an abundant number, since it is smaller than the sum of its proper divisors (821552760).

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

261523080 is a wasteful number, since it uses less digits than its factorization.

261523080 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 930 (or 917 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 261523080 is about 16171.6752378967. The cubic root of 261523080 is about 639.4942945250.

The spelling of 261523080 in words is "two hundred sixty-one million, five hundred twenty-three thousand, eighty".