124209521 has 2 divisors, whose sum is σ = 124209522. Its totient is φ = 124209520.

The previous prime is 124209509. The next prime is 124209551. The reversal of 124209521 is 125902421.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 105165025 + 19044496 = 10255^2 + 4364^2 .

It is an emirp because it is prime and its reverse (125902421) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 124209521 - 2⁶ = 124209457 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (124209551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 62104760 + 62104761.

It is an arithmetic number, because the mean of its divisors is an integer number (62104761).

Almost surely, 2^124209521 is an apocalyptic number.

It is an amenable number.

124209521 is a deficient number, since it is larger than the sum of its proper divisors (1).

124209521 is an equidigital number, since it uses as much as digits as its factorization.

124209521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 124209521 is about 11144.9325255921. The cubic root of 124209521 is about 498.9437984476.

The spelling of 124209521 in words is "one hundred twenty-four million, two hundred nine thousand, five hundred twenty-one".