261543144375541 has 8 divisors (see below), whose sum is σ = 300223219222080. Its totient is φ = 223192261655808.

The previous prime is 261543144375533. The next prime is 261543144375551. The reversal of 261543144375541 is 145573441345162.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 261543144375541 - 2³ = 261543144375533 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261543144375551) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 82298029996 + ... + 82298033173.

It is an arithmetic number, because the mean of its divisors is an integer number (37527902402760).

Almost surely, 2^{261543144375541} is an apocalyptic number.

It is an amenable number.

261543144375541 is a deficient number, since it is larger than the sum of its proper divisors (38680074846539).

261543144375541 is a wasteful number, since it uses less digits than its factorization.

261543144375541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164596063403.

The product of its digits is 24192000, while the sum is 55.

The spelling of 261543144375541 in words is "two hundred sixty-one trillion, five hundred forty-three billion, one hundred forty-four million, three hundred seventy-five thousand, five hundred forty-one".