121541509 has 2 divisors, whose sum is σ = 121541510. Its totient is φ = 121541508.

The previous prime is 121541501. The next prime is 121541543. The reversal of 121541509 is 905145121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 104550625 + 16990884 = 10225^2 + 4122^2 .

It is a cyclic number.

It is not a de Polignac number, because 121541509 - 2³ = 121541501 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121541501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60770754 + 60770755.

It is an arithmetic number, because the mean of its divisors is an integer number (60770755).

Almost surely, 2^121541509 is an apocalyptic number.

It is an amenable number.

121541509 is a deficient number, since it is larger than the sum of its proper divisors (1).

121541509 is an equidigital number, since it uses as much as digits as its factorization.

121541509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1800, while the sum is 28.

The square root of 121541509 is about 11024.5865682120. The cubic root of 121541509 is about 495.3454840802.

It can be divided in two parts, 1215 and 41509, that added together give a palindrome (42724).

The spelling of 121541509 in words is "one hundred twenty-one million, five hundred forty-one thousand, five hundred nine".