121585720 has 48 divisors (see below), whose sum is σ = 282766680. Its totient is φ = 47050560.

The previous prime is 121585699. The next prime is 121585721. The reversal of 121585720 is 27585121.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121585721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 36859 + ... + 40021.

Almost surely, 2^121585720 is an apocalyptic number.

121585720 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 121585720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (141383340).

121585720 is an abundant number, since it is smaller than the sum of its proper divisors (161180960).

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

121585720 is a wasteful number, since it uses less digits than its factorization.

121585720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3236 (or 3201 counting only the distinct ones).

The product of its (nonzero) digits is 5600, while the sum is 31.

The square root of 121585720 is about 11026.5914951085. The cubic root of 121585720 is about 495.4055378143.

The spelling of 121585720 in words is "one hundred twenty-one million, five hundred eighty-five thousand, seven hundred twenty".