1243411621 has 2 divisors, whose sum is σ = 1243411622. Its totient is φ = 1243411620.

The previous prime is 1243411619. The next prime is 1243411639. The reversal of 1243411621 is 1261143421.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 642622500 + 600789121 = 25350^2 + 24511^2 .

It is a cyclic number.

It is not a de Polignac number, because 1243411621 - 2¹ = 1243411619 is a prime.

Together with 1243411619, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1243411681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 621705810 + 621705811.

It is an arithmetic number, because the mean of its divisors is an integer number (621705811).

Almost surely, 2^1243411621 is an apocalyptic number.

It is an amenable number.

1243411621 is a deficient number, since it is larger than the sum of its proper divisors (1).

1243411621 is an equidigital number, since it uses as much as digits as its factorization.

1243411621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1152, while the sum is 25.

The square root of 1243411621 is about 35262.0422125548. The cubic root of 1243411621 is about 1075.3214458946.

The spelling of 1243411621 in words is "one billion, two hundred forty-three million, four hundred eleven thousand, six hundred twenty-one".