66999901212 has 72 divisors (see below), whose sum is σ = 173544239232. Its totient is φ = 21781977600.

The previous prime is 66999901201. The next prime is 66999901219. The reversal of 66999901212 is 21210999966.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66999901219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8071048 + ... + 8079344.

It is an arithmetic number, because the mean of its divisors is an integer number (2410336656).

Almost surely, 2^66999901212 is an apocalyptic number.

It is an amenable number.

66999901212 is an abundant number, since it is smaller than the sum of its proper divisors (106544338020).

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

66999901212 is a wasteful number, since it uses less digits than its factorization.

66999901212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13819 (or 13814 counting only the distinct ones).

The product of its (nonzero) digits is 944784, while the sum is 54.

The spelling of 66999901212 in words is "sixty-six billion, nine hundred ninety-nine million, nine hundred one thousand, two hundred twelve".