1242265643 has 2 divisors, whose sum is σ = 1242265644. Its totient is φ = 1242265642.

The previous prime is 1242265637. The next prime is 1242265669. The reversal of 1242265643 is 3465622421.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1242265643 - 2⁶ = 1242265579 is a prime.

It is not a weakly prime, because it can be changed into another prime (1242265603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 621132821 + 621132822.

It is an arithmetic number, because the mean of its divisors is an integer number (621132822).

Almost surely, 2^1242265643 is an apocalyptic number.

1242265643 is a deficient number, since it is larger than the sum of its proper divisors (1).

1242265643 is an equidigital number, since it uses as much as digits as its factorization.

1242265643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 69120, while the sum is 35.

The square root of 1242265643 is about 35245.7890108875. The cubic root of 1242265643 is about 1074.9909912351.

The spelling of 1242265643 in words is "one billion, two hundred forty-two million, two hundred sixty-five thousand, six hundred forty-three".