121666212 has 144 divisors (see below), whose sum is σ = 348566400. Its totient is φ = 36951552.

The previous prime is 121666189. The next prime is 121666213. The reversal of 121666212 is 212666121.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121666213) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 611289 + ... + 611487.

It is an arithmetic number, because the mean of its divisors is an integer number (2420600).

Almost surely, 2^121666212 is an apocalyptic number.

121666212 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 121666212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (174283200).

121666212 is an abundant number, since it is smaller than the sum of its proper divisors (226900188).

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

121666212 is a wasteful number, since it uses less digits than its factorization.

121666212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 272 (or 258 counting only the distinct ones).

The product of its digits is 1728, while the sum is 27.

The square root of 121666212 is about 11030.2407951957. The cubic root of 121666212 is about 495.5148362478.

Subtracting 121666212 from its reverse (212666121), we obtain a palindrome (90999909).

The spelling of 121666212 in words is "one hundred twenty-one million, six hundred sixty-six thousand, two hundred twelve".