121640660 has 24 divisors (see below), whose sum is σ = 268890720. Its totient is φ = 46095264.

The previous prime is 121640657. The next prime is 121640677. The reversal of 121640660 is 66046121.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 159674 + ... + 160433.

It is an arithmetic number, because the mean of its divisors is an integer number (11203780).

Almost surely, 2^121640660 is an apocalyptic number.

121640660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121640660 is an abundant number, since it is smaller than the sum of its proper divisors (147250060).

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

121640660 is a wasteful number, since it uses less digits than its factorization.

121640660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 320135 (or 320133 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 121640660 is about 11029.0824641037. The cubic root of 121640660 is about 495.4801449358.

Adding to 121640660 its reverse (66046121), we get a palindrome (187686781).

The spelling of 121640660 in words is "one hundred twenty-one million, six hundred forty thousand, six hundred sixty".