121220545 has 4 divisors (see below), whose sum is σ = 145464660. Its totient is φ = 96976432.

The previous prime is 121220543. The next prime is 121220563. The reversal of 121220545 is 545022121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 545022121 = 7 ⋅77860303.

It can be written as a sum of positive squares in 2 ways, for example, as 33779344 + 87441201 = 5812^2 + 9351^2 .

It is a cyclic number.

It is not a de Polignac number, because 121220545 - 2¹ = 121220543 is a prime.

It is not an unprimeable number, because it can be changed into a prime (121220543) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12122050 + ... + 12122059.

It is an arithmetic number, because the mean of its divisors is an integer number (36366165).

Almost surely, 2^121220545 is an apocalyptic number.

It is an amenable number.

121220545 is a deficient number, since it is larger than the sum of its proper divisors (24244115).

121220545 is an equidigital number, since it uses as much as digits as its factorization.

121220545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24244114.

The product of its (nonzero) digits is 800, while the sum is 22.

The square root of 121220545 is about 11010.0202088825. The cubic root of 121220545 is about 494.9090674036.

Adding to 121220545 its reverse (545022121), we get a palindrome (666242666).

The spelling of 121220545 in words is "one hundred twenty-one million, two hundred twenty thousand, five hundred forty-five".