121204752545809 has 27 divisors (see below), whose sum is σ = 129221293050801. Its totient is φ = 113668851614400.

The previous prime is 121204752545803. The next prime is 121204752545827. The reversal of 121204752545809 is 908545257402121.

The square root of 121204752545809 is 11009303.

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 1355419850625 + 119849332695184 = 1164225^2 + 10947572^2 .

It is not a de Polignac number, because 121204752545809 - 2⁹ = 121204752545297 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 121204752545809.

It is not an unprimeable number, because it can be changed into a prime (121204752545803) 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, 21126849589 + ... + 21126855325.

Almost surely, 2^{121204752545809} is an apocalyptic number.

121204752545809 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

121204752545809 is the 11009303-rd square number.

121204752545809 is the 5504652-nd centered octagonal number.

It is an amenable number.

121204752545809 is a deficient number, since it is larger than the sum of its proper divisors (8016540504992).

121204752545809 is an frugal number, since it uses more digits than its factorization.

121204752545809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11714 (or 5857 counting only the distinct ones).

The product of its (nonzero) digits is 8064000, while the sum is 55.

The spelling of 121204752545809 in words is "one hundred twenty-one trillion, two hundred four billion, seven hundred fifty-two million, five hundred forty-five thousand, eight hundred nine".