1566216171551 has 4 divisors (see below), whose sum is σ = 1566261912072. Its totient is φ = 1566170431032.

The previous prime is 1566216171511. The next prime is 1566216171581. The reversal of 1566216171551 is 1551716126651.

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 1566216171551 - 2¹⁸ = 1566215909407 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1566216171496 and 1566216171505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1566216171511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22818860 + ... + 22887393.

It is an arithmetic number, because the mean of its divisors is an integer number (391565478018).

Almost surely, 2^{1566216171551} is an apocalyptic number.

1566216171551 is a deficient number, since it is larger than the sum of its proper divisors (45740521).

1566216171551 is an equidigital number, since it uses as much as digits as its factorization.

1566216171551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45740520.

The product of its digits is 378000, while the sum is 47.

The spelling of 1566216171551 in words is "one trillion, five hundred sixty-six billion, two hundred sixteen million, one hundred seventy-one thousand, five hundred fifty-one".