261088380 has 288 divisors, whose sum is σ = 990259200. Its totient is φ = 55931904.

The previous prime is 261088351. The next prime is 261088403. The reversal of 261088380 is 83880162.

261088380 is a `hidden beast` number, since 2 + 610 + 8 + 8 + 38 + 0 = 666.

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 95 ways as a sum of consecutive naturals, for example, 1092301 + ... + 1092539.

It is an arithmetic number, because the mean of its divisors is an integer number (3438400).

Almost surely, 2^261088380 is an apocalyptic number.

261088380 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 261088380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (495129600).

261088380 is an abundant number, since it is smaller than the sum of its proper divisors (729170820).

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

261088380 is a wasteful number, since it uses less digits than its factorization.

261088380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 298 (or 273 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 261088380 is about 16158.2294822174. The cubic root of 261088380 is about 639.1397785426.

The spelling of 261088380 in words is "two hundred sixty-one million, eighty-eight thousand, three hundred eighty".