243051221389 has 2 divisors, whose sum is σ = 243051221390. Its totient is φ = 243051221388.

The previous prime is 243051221341. The next prime is 243051221449. The reversal of 243051221389 is 983122150342.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 173666393289 + 69384828100 = 416733^2 + 263410^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-243051221389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (243051321389) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121525610694 + 121525610695.

It is an arithmetic number, because the mean of its divisors is an integer number (121525610695).

Almost surely, 2^243051221389 is an apocalyptic number.

It is an amenable number.

243051221389 is a deficient number, since it is larger than the sum of its proper divisors (1).

243051221389 is an equidigital number, since it uses as much as digits as its factorization.

243051221389 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 103680, while the sum is 40.

The spelling of 243051221389 in words is "two hundred forty-three billion, fifty-one million, two hundred twenty-one thousand, three hundred eighty-nine".