144661721891 has 2 divisors, whose sum is σ = 144661721892. Its totient is φ = 144661721890.

The previous prime is 144661721861. The next prime is 144661721957. The reversal of 144661721891 is 198127166441.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 144661721891 - 2¹⁰ = 144661720867 is a prime.

It is not a weakly prime, because it can be changed into another prime (144661721821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 72330860945 + 72330860946.

It is an arithmetic number, because the mean of its divisors is an integer number (72330860946).

Almost surely, 2^144661721891 is an apocalyptic number.

144661721891 is a deficient number, since it is larger than the sum of its proper divisors (1).

144661721891 is an equidigital number, since it uses as much as digits as its factorization.

144661721891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 580608, while the sum is 50.

The spelling of 144661721891 in words is "one hundred forty-four billion, six hundred sixty-one million, seven hundred twenty-one thousand, eight hundred ninety-one".