144865781 has 2 divisors, whose sum is σ = 144865782. Its totient is φ = 144865780.

The previous prime is 144865771. The next prime is 144865807. The reversal of 144865781 is 187568441.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 144240100 + 625681 = 12010^2 + 791^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-144865781 is a prime.

It is a super-2 number, since 2×144865781² = 41972189009479922, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (144865741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 72432890 + 72432891.

It is an arithmetic number, because the mean of its divisors is an integer number (72432891).

Almost surely, 2^144865781 is an apocalyptic number.

It is an amenable number.

144865781 is a deficient number, since it is larger than the sum of its proper divisors (1).

144865781 is an equidigital number, since it uses as much as digits as its factorization.

144865781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 215040, while the sum is 44.

The square root of 144865781 is about 12036.0201478728. The cubic root of 144865781 is about 525.1966380561.

The spelling of 144865781 in words is "one hundred forty-four million, eight hundred sixty-five thousand, seven hundred eighty-one".