16661216656212 has 24 divisors (see below), whose sum is σ = 38938977016800. Its totient is φ = 5544766768416.

The previous prime is 16661216656087. The next prime is 16661216656241. The reversal of 16661216656212 is 21265661216661.

It is a super-2 number, since 2×16661216656212² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1121506887 + ... + 1121521742.

It is an arithmetic number, because the mean of its divisors is an integer number (1622457375700).

Almost surely, 2^{16661216656212} is an apocalyptic number.

16661216656212 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

16661216656212 is an abundant number, since it is smaller than the sum of its proper divisors (22277760360588).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

16661216656212 is a wasteful number, since it uses less digits than its factorization.

16661216656212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2243029255 (or 2243029253 counting only the distinct ones).

The product of its digits is 1866240, while the sum is 51.

The spelling of 16661216656212 in words is "sixteen trillion, six hundred sixty-one billion, two hundred sixteen million, six hundred fifty-six thousand, two hundred twelve".