121505581 has 2 divisors, whose sum is σ = 121505582. Its totient is φ = 121505580.

The previous prime is 121505569. The next prime is 121505617. The reversal of 121505581 is 185505121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 112148100 + 9357481 = 10590^2 + 3059^2 .

It is a cyclic number.

It is not a de Polignac number, because 121505581 - 2⁷ = 121505453 is a prime.

It is a super-2 number, since 2×121505581² = 29527212428295122, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121505561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60752790 + 60752791.

It is an arithmetic number, because the mean of its divisors is an integer number (60752791).

Almost surely, 2^121505581 is an apocalyptic number.

It is an amenable number.

121505581 is a deficient number, since it is larger than the sum of its proper divisors (1).

121505581 is an equidigital number, since it uses as much as digits as its factorization.

121505581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2000, while the sum is 28.

The square root of 121505581 is about 11022.9569989182. The cubic root of 121505581 is about 495.2966707802.

The spelling of 121505581 in words is "one hundred twenty-one million, five hundred five thousand, five hundred eighty-one".