1681844513 has 2 divisors, whose sum is σ = 1681844514. Its totient is φ = 1681844512.

The previous prime is 1681844449. The next prime is 1681844551. The reversal of 1681844513 is 3154481861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1623122944 + 58721569 = 40288^2 + 7663^2 .

It is a cyclic number.

It is not a de Polignac number, because 1681844513 - 2⁶ = 1681844449 is a prime.

It is not a weakly prime, because it can be changed into another prime (1681844573) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 840922256 + 840922257.

It is an arithmetic number, because the mean of its divisors is an integer number (840922257).

Almost surely, 2^1681844513 is an apocalyptic number.

It is an amenable number.

1681844513 is a deficient number, since it is larger than the sum of its proper divisors (1).

1681844513 is an equidigital number, since it uses as much as digits as its factorization.

1681844513 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 92160, while the sum is 41.

The square root of 1681844513 is about 41010.2976458352. The cubic root of 1681844513 is about 1189.2192965583.

The spelling of 1681844513 in words is "one billion, six hundred eighty-one million, eight hundred forty-four thousand, five hundred thirteen".