1815572849 has 2 divisors, whose sum is σ = 1815572850. Its totient is φ = 1815572848.

The previous prime is 1815572833. The next prime is 1815572933. The reversal of 1815572849 is 9482755181.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1632160000 + 183412849 = 40400^2 + 13543^2 .

It is a cyclic number.

It is not a de Polignac number, because 1815572849 - 2⁴ = 1815572833 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1815572797 and 1815572806.

It is not a weakly prime, because it can be changed into another prime (1815572819) 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, 907786424 + 907786425.

It is an arithmetic number, because the mean of its divisors is an integer number (907786425).

Almost surely, 2^1815572849 is an apocalyptic number.

It is an amenable number.

1815572849 is a deficient number, since it is larger than the sum of its proper divisors (1).

1815572849 is an equidigital number, since it uses as much as digits as its factorization.

1815572849 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 806400, while the sum is 50.

The square root of 1815572849 is about 42609.5394131408. The cubic root of 1815572849 is about 1219.9383756833.

The spelling of 1815572849 in words is "one billion, eight hundred fifteen million, five hundred seventy-two thousand, eight hundred forty-nine".