261268648342656 has 128 divisors (see below), whose sum is σ = 694308516480000. Its totient is φ = 87050195460096.

The previous prime is 261268648342643. The next prime is 261268648342687. The reversal of 261268648342656 is 656243846862162.

It is a tau number, because it is divible by the number of its divisors (128).

It is a super-2 number, since 2×261268648342656² (a number of 30 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14588669830 + ... + 14588687738.

It is an arithmetic number, because the mean of its divisors is an integer number (5424285285000).

Almost surely, 2^{261268648342656} is an apocalyptic number.

It is an amenable number.

261268648342656 is an abundant number, since it is smaller than the sum of its proper divisors (433039868137344).

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

261268648342656 is a wasteful number, since it uses less digits than its factorization.

261268648342656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32974 (or 32962 counting only the distinct ones).

The product of its digits is 955514880, while the sum is 69.

The spelling of 261268648342656 in words is "two hundred sixty-one trillion, two hundred sixty-eight billion, six hundred forty-eight million, three hundred forty-two thousand, six hundred fifty-six".