1815797749 has 2 divisors, whose sum is σ = 1815797750. Its totient is φ = 1815797748.

The previous prime is 1815797741. The next prime is 1815797773. The reversal of 1815797749 is 9477975181.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 978563524 + 837234225 = 31282^2 + 28935^2 .

It is a cyclic number.

It is not a de Polignac number, because 1815797749 - 2³ = 1815797741 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1815797693 and 1815797702.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1815797741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 907898874 + 907898875.

It is an arithmetic number, because the mean of its divisors is an integer number (907898875).

Almost surely, 2^1815797749 is an apocalyptic number.

It is an amenable number.

1815797749 is a deficient number, since it is larger than the sum of its proper divisors (1).

1815797749 is an equidigital number, since it uses as much as digits as its factorization.

1815797749 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4445280, while the sum is 58.

The square root of 1815797749 is about 42612.1784118109. The cubic root of 1815797749 is about 1219.9887459770.

The spelling of 1815797749 in words is "one billion, eight hundred fifteen million, seven hundred ninety-seven thousand, seven hundred forty-nine".