20666123212 has 12 divisors (see below), whose sum is σ = 41332246480. Its totient is φ = 8856909936.

The previous prime is 20666123207. The next prime is 20666123221. The reversal of 20666123212 is 21232166602.

20666123212 is an admirable number.

It is a super-2 number, since 2×20666123212² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 369037887 + ... + 369037942.

Almost surely, 2^20666123212 is an apocalyptic number.

It is an amenable number.

20666123212 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

20666123212 is a wasteful number, since it uses less digits than its factorization.

20666123212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 738075840 (or 738075838 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 31.

Adding to 20666123212 its reverse (21232166602), we get a palindrome (41898289814).

The spelling of 20666123212 in words is "twenty billion, six hundred sixty-six million, one hundred twenty-three thousand, two hundred twelve".