121720824 has 48 divisors (see below), whose sum is σ = 338577720. Its totient is φ = 39476160.

The previous prime is 121720817. The next prime is 121720873. The reversal of 121720824 is 428027121.

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, 20182 + ... + 25509.

Almost surely, 2^121720824 is an apocalyptic number.

It is an amenable number.

121720824 is an abundant number, since it is smaller than the sum of its proper divisors (216856896).

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

121720824 is a wasteful number, since it uses less digits than its factorization.

121720824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45740 (or 45733 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 27.

The square root of 121720824 is about 11032.7160753823. The cubic root of 121720824 is about 495.5889653147.

Adding to 121720824 its reverse (428027121), we get a palindrome (549747945).

The spelling of 121720824 in words is "one hundred twenty-one million, seven hundred twenty thousand, eight hundred twenty-four".