16506145661 has 16 divisors (see below), whose sum is σ = 17641430400. Its totient is φ = 15409994688.

The previous prime is 16506145637. The next prime is 16506145681. The reversal of 16506145661 is 16654160561.

It is a cyclic number.

It is not a de Polignac number, because 16506145661 - 2¹⁰ = 16506144637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16506145681) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 118835 + ... + 217103.

It is an arithmetic number, because the mean of its divisors is an integer number (1102589400).

Almost surely, 2^16506145661 is an apocalyptic number.

It is an amenable number.

16506145661 is a deficient number, since it is larger than the sum of its proper divisors (1135284739).

16506145661 is a wasteful number, since it uses less digits than its factorization.

16506145661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98468.

The product of its (nonzero) digits is 129600, while the sum is 41.

The spelling of 16506145661 in words is "sixteen billion, five hundred six million, one hundred forty-five thousand, six hundred sixty-one".