16505043531 has 4 divisors (see below), whose sum is σ = 22006724712. Its totient is φ = 11003362352.

The previous prime is 16505043493. The next prime is 16505043553. The reversal of 16505043531 is 13534050561.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 16505043531 - 2⁹ = 16505043019 is a prime.

It is a super-3 number, since 3×16505043531³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a junction number, because it is equal to n+sod(n) for n = 16505043492 and 16505043501.

It is not an unprimeable number, because it can be changed into a prime (16505043131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2750840586 + ... + 2750840591.

It is an arithmetic number, because the mean of its divisors is an integer number (5501681178).

Almost surely, 2^16505043531 is an apocalyptic number.

16505043531 is a deficient number, since it is larger than the sum of its proper divisors (5501681181).

16505043531 is an equidigital number, since it uses as much as digits as its factorization.

16505043531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5501681180.

The product of its (nonzero) digits is 27000, while the sum is 33.

The spelling of 16505043531 in words is "sixteen billion, five hundred five million, forty-three thousand, five hundred thirty-one".