1242124021 has 2 divisors, whose sum is σ = 1242124022. Its totient is φ = 1242124020.

The previous prime is 1242124007. The next prime is 1242124067. The reversal of 1242124021 is 1204212421.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1218708100 + 23415921 = 34910^2 + 4839^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1242124021 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1242124021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1242124321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 621062010 + 621062011.

It is an arithmetic number, because the mean of its divisors is an integer number (621062011).

Almost surely, 2^1242124021 is an apocalyptic number.

It is an amenable number.

1242124021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1242124021 is an equidigital number, since it uses as much as digits as its factorization.

1242124021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 256, while the sum is 19.

The square root of 1242124021 is about 35243.7798909254. The cubic root of 1242124021 is about 1074.9501389529.

Adding to 1242124021 its reverse (1204212421), we get a palindrome (2446336442).

The spelling of 1242124021 in words is "one billion, two hundred forty-two million, one hundred twenty-four thousand, twenty-one".