121731120 has 320 divisors, whose sum is σ = 489968640. Its totient is φ = 27205632.

The previous prime is 121731107. The next prime is 121731121. The reversal of 121731120 is 21137121.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 121731093 and 121731102.

It is not an unprimeable number, because it can be changed into a prime (121731121) by changing a digit.

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 63 ways as a sum of consecutive naturals, for example, 1254912 + ... + 1255008.

It is an arithmetic number, because the mean of its divisors is an integer number (1531152).

Almost surely, 2^121731120 is an apocalyptic number.

121731120 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 121731120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (244984320).

121731120 is an abundant number, since it is smaller than the sum of its proper divisors (368237520).

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

121731120 is a wasteful number, since it uses less digits than its factorization.

121731120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 209 (or 197 counting only the distinct ones).

The product of its (nonzero) digits is 84, while the sum is 18.

The square root of 121731120 is about 11033.1826777227. The cubic root of 121731120 is about 495.6029383829.

Adding to 121731120 its reverse (21137121), we get a palindrome (142868241).

The spelling of 121731120 in words is "one hundred twenty-one million, seven hundred thirty-one thousand, one hundred twenty".