121666560 has 132 divisors (see below), whose sum is σ = 393564408. Its totient is φ = 32079872.

The previous prime is 121666547. The next prime is 121666579. The reversal of 121666560 is 65666121.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1366996 + ... + 1367084.

Almost surely, 2^121666560 is an apocalyptic number.

121666560 is a gapful number since it is divisible by the number (10) 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 121666560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (196782204).

121666560 is an abundant number, since it is smaller than the sum of its proper divisors (271897848).

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

121666560 is an frugal number, since it uses more digits than its factorization.

121666560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 206 (or 99 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 33.

The square root of 121666560 is about 11030.2565699987. The cubic root of 121666560 is about 495.5153086852.

It can be divided in two parts, 1216 and 66560, that added together give a palindrome (67776).

The spelling of 121666560 in words is "one hundred twenty-one million, six hundred sixty-six thousand, five hundred sixty".