16661731223453 has 4 divisors (see below), whose sum is σ = 17538664445760. Its totient is φ = 15784798001148.

The previous prime is 16661731223413. The next prime is 16661731223587. The reversal of 16661731223453 is 35432213716661.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 16661731223453 - 2¹⁰ = 16661731222429 is a prime.

It is a super-2 number, since 2×16661731223453² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16661731223413) 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, 438466611125 + ... + 438466611162.

It is an arithmetic number, because the mean of its divisors is an integer number (4384666111440).

Almost surely, 2^{16661731223453} is an apocalyptic number.

It is an amenable number.

16661731223453 is a deficient number, since it is larger than the sum of its proper divisors (876933222307).

16661731223453 is an equidigital number, since it uses as much as digits as its factorization.

16661731223453 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 876933222306.

The product of its digits is 3265920, while the sum is 50.

The spelling of 16661731223453 in words is "sixteen trillion, six hundred sixty-one billion, seven hundred thirty-one million, two hundred twenty-three thousand, four hundred fifty-three".