1240012021 has 2 divisors, whose sum is σ = 1240012022. Its totient is φ = 1240012020.

The previous prime is 1240012019. The next prime is 1240012049. The reversal of 1240012021 is 1202100421.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 645871396 + 594140625 = 25414^2 + 24375^2 .

It is an emirp because it is prime and its reverse (1202100421) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1240012021 - 2¹ = 1240012019 is a prime.

Together with 1240012019, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 1240011992 and 1240012010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1240012001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 620006010 + 620006011.

It is an arithmetic number, because the mean of its divisors is an integer number (620006011).

Almost surely, 2^1240012021 is an apocalyptic number.

It is an amenable number.

1240012021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1240012021 is an equidigital number, since it uses as much as digits as its factorization.

1240012021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 1240012021 is about 35213.8044096346. The cubic root of 1240012021 is about 1074.3405426460.

Adding to 1240012021 its reverse (1202100421), we get a palindrome (2442112442).

The spelling of 1240012021 in words is "one billion, two hundred forty million, twelve thousand, twenty-one".