261543746101365 has 96 divisors (see below), whose sum is σ = 559056184727040. Its totient is φ = 110148883250688.

The previous prime is 261543746101349. The next prime is 261543746101387. The reversal of 261543746101365 is 563101647345162.

261543746101365 is a `hidden beast` number, since 2 + 6 + 1 + 5 + 4 + 3 + 7 + 4 + 610 + 13 + 6 + 5 = 666.

It is not a de Polignac number, because 261543746101365 - 2⁴ = 261543746101349 is a prime.

It is a super-2 number, since 2×261543746101365² (a number of 30 digits) contains 22 as substring.

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, 60655377 + ... + 64824086.

It is an arithmetic number, because the mean of its divisors is an integer number (5823501924240).

Almost surely, 2^{261543746101365} is an apocalyptic number.

It is an amenable number.

261543746101365 is an abundant number, since it is smaller than the sum of its proper divisors (297512438625675).

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

261543746101365 is a wasteful number, since it uses less digits than its factorization.

261543746101365 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125480003 (or 125480000 counting only the distinct ones).

The product of its (nonzero) digits is 10886400, while the sum is 54.

The spelling of 261543746101365 in words is "two hundred sixty-one trillion, five hundred forty-three billion, seven hundred forty-six million, one hundred one thousand, three hundred sixty-five".