16501010561 has 8 divisors (see below), whose sum is σ = 18866806464. Its totient is φ = 14137341840.

The previous prime is 16501010531. The next prime is 16501010563.

16501010561 is nontrivially palindromic in base 10.

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 16501010561 - 2¹⁴ = 16500994177 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 16501010561.

It is not an unprimeable number, because it can be changed into a prime (16501010563) 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, 515135 + ... + 546228.

It is an arithmetic number, because the mean of its divisors is an integer number (2358350808).

Almost surely, 2^16501010561 is an apocalyptic number.

It is an amenable number.

16501010561 is a deficient number, since it is larger than the sum of its proper divisors (2365795903).

16501010561 is a wasteful number, since it uses less digits than its factorization.

16501010561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1063591.

The product of its (nonzero) digits is 900, while the sum is 26.

It can be divided in two parts, 165010 and 10561, that added together give a palindrome (175571).

The spelling of 16501010561 in words is "sixteen billion, five hundred one million, ten thousand, five hundred sixty-one".