261958124137680 has 240 divisors, whose sum is σ = 951992102355840. Its totient is φ = 66818304013824.

The previous prime is 261958124137673. The next prime is 261958124137709. The reversal of 261958124137680 is 86731421859162.

It is a happy number.

261958124137680 is a `hidden beast` number, since 2 + 6 + 1 + 9 + 581 + 2 + 41 + 3 + 7 + 6 + 8 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 292492275 + ... + 293386514.

It is an arithmetic number, because the mean of its divisors is an integer number (3966633759816).

It is a 2-persistent number, because it is pandigital, and so is 2⋅261958124137680 = 523916248275360, but 3⋅261958124137680 = 785874372413040 is not.

Almost surely, 2^{261958124137680} is an apocalyptic number.

261958124137680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261958124137680 is an abundant number, since it is smaller than the sum of its proper divisors (690033978218160).

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

261958124137680 is a wasteful number, since it uses less digits than its factorization.

261958124137680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 585878840 (or 585878822 counting only the distinct ones).

The product of its (nonzero) digits is 34836480, while the sum is 63.

The spelling of 261958124137680 in words is "two hundred sixty-one trillion, nine hundred fifty-eight billion, one hundred twenty-four million, one hundred thirty-seven thousand, six hundred eighty".