154543821561 has 16 divisors (see below), whose sum is σ = 242421681600. Its totient is φ = 96968672064.

The previous prime is 154543821491. The next prime is 154543821569. The reversal of 154543821561 is 165128345451.

154543821561 is a `hidden beast` number, since 1 + 5 + 4 + 5 + 4 + 3 + 82 + 1 + 561 = 666.

It is not a de Polignac number, because 154543821561 - 2¹¹ = 154543819513 is a prime.

It is not an unprimeable number, because it can be changed into a prime (154543821569) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 168347931 + ... + 168348848.

It is an arithmetic number, because the mean of its divisors is an integer number (15151355100).

Almost surely, 2^154543821561 is an apocalyptic number.

It is an amenable number.

154543821561 is a deficient number, since it is larger than the sum of its proper divisors (87877860039).

154543821561 is a wasteful number, since it uses less digits than its factorization.

154543821561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 336696805 (or 336696799 counting only the distinct ones).

The product of its digits is 576000, while the sum is 45.

The spelling of 154543821561 in words is "one hundred fifty-four billion, five hundred forty-three million, eight hundred twenty-one thousand, five hundred sixty-one".