1815339649 has 2 divisors, whose sum is σ = 1815339650. Its totient is φ = 1815339648.

The previous prime is 1815339613. The next prime is 1815339719. The reversal of 1815339649 is 9469335181.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1766689024 + 48650625 = 42032^2 + 6975^2 .

It is a cyclic number.

It is not a de Polignac number, because 1815339649 - 2⁷ = 1815339521 is a prime.

It is not a weakly prime, because it can be changed into another prime (1815339049) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 907669824 + 907669825.

It is an arithmetic number, because the mean of its divisors is an integer number (907669825).

Almost surely, 2^1815339649 is an apocalyptic number.

It is an amenable number.

1815339649 is a deficient number, since it is larger than the sum of its proper divisors (1).

1815339649 is an equidigital number, since it uses as much as digits as its factorization.

1815339649 is an evil number, because the sum of its binary digits is even.

The product of its digits is 699840, while the sum is 49.

The square root of 1815339649 is about 42606.8028488409. The cubic root of 1815339649 is about 1219.8861420663.

The spelling of 1815339649 in words is "one billion, eight hundred fifteen million, three hundred thirty-nine thousand, six hundred forty-nine".