16644163752551 has 2 divisors, whose sum is σ = 16644163752552. Its totient is φ = 16644163752550.

The previous prime is 16644163752529. The next prime is 16644163752617. The reversal of 16644163752551 is 15525736144661.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 16644163752551 - 2⁴² = 12246117241447 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16644163752521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8322081876275 + 8322081876276.

It is an arithmetic number, because the mean of its divisors is an integer number (8322081876276).

Almost surely, 2^{16644163752551} is an apocalyptic number.

16644163752551 is a deficient number, since it is larger than the sum of its proper divisors (1).

16644163752551 is an equidigital number, since it uses as much as digits as its factorization.

16644163752551 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18144000, while the sum is 56.

The spelling of 16644163752551 in words is "sixteen trillion, six hundred forty-four billion, one hundred sixty-three million, seven hundred fifty-two thousand, five hundred fifty-one".