121061547721 has 27 divisors (see below), whose sum is σ = 130559925717. Its totient is φ = 112231203840.

The previous prime is 121061547707. The next prime is 121061547767. The reversal of 121061547721 is 127745160121.

The square root of 121061547721 is 347939.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 7087787721 + 113973760000 = 84189^2 + 337600^2 .

It is not a de Polignac number, because 121061547721 - 2⁵ = 121061547689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121061547221) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 573751306 + ... + 573751516.

Almost surely, 2^121061547721 is an apocalyptic number.

121061547721 is the 347939-th square number.

121061547721 is the 173970-th centered octagonal number.

It is an amenable number.

121061547721 is a deficient number, since it is larger than the sum of its proper divisors (9498377996).

121061547721 is an frugal number, since it uses more digits than its factorization.

121061547721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 650 (or 325 counting only the distinct ones).

The product of its (nonzero) digits is 23520, while the sum is 37.

The spelling of 121061547721 in words is "one hundred twenty-one billion, sixty-one million, five hundred forty-seven thousand, seven hundred twenty-one".