1813840729 has 2 divisors, whose sum is σ = 1813840730. Its totient is φ = 1813840728.

The previous prime is 1813840667. The next prime is 1813840759. The reversal of 1813840729 is 9270483181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1807950400 + 5890329 = 42520^2 + 2427^2 .

It is a cyclic number.

It is not a de Polignac number, because 1813840729 - 2⁷ = 1813840601 is a prime.

It is not a weakly prime, because it can be changed into another prime (1813840759) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 906920364 + 906920365.

It is an arithmetic number, because the mean of its divisors is an integer number (906920365).

Almost surely, 2^1813840729 is an apocalyptic number.

It is an amenable number.

1813840729 is a deficient number, since it is larger than the sum of its proper divisors (1).

1813840729 is an equidigital number, since it uses as much as digits as its factorization.

1813840729 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96768, while the sum is 43.

The square root of 1813840729 is about 42589.2090675561. The cubic root of 1813840729 is about 1219.5502976173.

The spelling of 1813840729 in words is "one billion, eight hundred thirteen million, eight hundred forty thousand, seven hundred twenty-nine".