166551616561511 has 32 divisors (see below), whose sum is σ = 190672110754560. Its totient is φ = 144471810802176.

The previous prime is 166551616561487. The next prime is 166551616561531. The reversal of 166551616561511 is 115165616155661.

It is not a de Polignac number, because 166551616561511 - 2¹⁰ = 166551616560487 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166551616561531) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 91395320 + ... + 93199826.

It is an arithmetic number, because the mean of its divisors is an integer number (5958503461080).

Almost surely, 2^{166551616561511} is an apocalyptic number.

166551616561511 is a deficient number, since it is larger than the sum of its proper divisors (24120494193049).

166551616561511 is a wasteful number, since it uses less digits than its factorization.

166551616561511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1812303.

The product of its digits is 4860000, while the sum is 56.

The spelling of 166551616561511 in words is "one hundred sixty-six trillion, five hundred fifty-one billion, six hundred sixteen million, five hundred sixty-one thousand, five hundred eleven".