261303007680 has 1344 divisors, whose sum is σ = 1106418733056. Its totient is φ = 55738368000.

The previous prime is 261303007673. The next prime is 261303007699. The reversal of 261303007680 is 86700303162.

It is a happy number.

261303007680 is a `hidden beast` number, since 2 + 613 + 0 + 30 + 0 + 7 + 6 + 8 + 0 = 666.

It is a super-2 number, since 2×261303007680² (a number of 24 digits) contains 22 as substring.

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 pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 1238402775 + ... + 1238402985.

It is an arithmetic number, because the mean of its divisors is an integer number (823228224).

Almost surely, 2^261303007680 is an apocalyptic number.

261303007680 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 261303007680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (553209366528).

261303007680 is an abundant number, since it is smaller than the sum of its proper divisors (845115725376).

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

261303007680 is a wasteful number, since it uses less digits than its factorization.

261303007680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 386 (or 373 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 36.

The spelling of 261303007680 in words is "two hundred sixty-one billion, three hundred three million, seven thousand, six hundred eighty".