16616521646653 has 4 divisors (see below), whose sum is σ = 17189505151740. Its totient is φ = 16043538141568.

The previous prime is 16616521646597. The next prime is 16616521646731. The reversal of 16616521646653 is 35664612561661.

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

It can be written as a sum of positive squares in 2 ways, for example, as 12619169208409 + 3997352438244 = 3552347^2 + 1999338^2 .

It is a cyclic number.

It is not a de Polignac number, because 16616521646653 - 2¹³ = 16616521638461 is a prime.

It is a super-2 number, since 2×16616521646653² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16616521646353) 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, 286491752500 + ... + 286491752557.

It is an arithmetic number, because the mean of its divisors is an integer number (4297376287935).

Almost surely, 2^{16616521646653} is an apocalyptic number.

It is an amenable number.

16616521646653 is a deficient number, since it is larger than the sum of its proper divisors (572983505087).

16616521646653 is an equidigital number, since it uses as much as digits as its factorization.

16616521646653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 572983505086.

The product of its digits is 27993600, while the sum is 58.

The spelling of 16616521646653 in words is "sixteen trillion, six hundred sixteen billion, five hundred twenty-one million, six hundred forty-six thousand, six hundred fifty-three".