121720064 has 18 divisors (see below), whose sum is σ = 242965170. Its totient is φ = 60859904.

The previous prime is 121720031. The next prime is 121720069. The reversal of 121720064 is 460027121.

It can be written as a sum of positive squares in only one way, i.e., 114918400 + 6801664 = 10720^2 + 2608^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121720069) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 237479 + ... + 237990.

It is an arithmetic number, because the mean of its divisors is an integer number (13498065).

Almost surely, 2^121720064 is an apocalyptic number.

It is an amenable number.

121720064 is a deficient number, since it is larger than the sum of its proper divisors (121245106).

121720064 is an frugal number, since it uses more digits than its factorization.

121720064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 475485 (or 475471 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 23.

The square root of 121720064 is about 11032.6816323141. The cubic root of 121720064 is about 495.5879338604.

Adding to 121720064 its reverse (460027121), we get a palindrome (581747185).

The spelling of 121720064 in words is "one hundred twenty-one million, seven hundred twenty thousand, sixty-four".