1811593481 has 2 divisors, whose sum is σ = 1811593482. Its totient is φ = 1811593480.

The previous prime is 1811593463. The next prime is 1811593493. The reversal of 1811593481 is 1843951181.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1679688256 + 131905225 = 40984^2 + 11485^2 .

It is an emirp because it is prime and its reverse (1843951181) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1811593481 is a prime.

It is a super-2 number, since 2×1811593481² = 6563741880803394722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1811593411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 905796740 + 905796741.

It is an arithmetic number, because the mean of its divisors is an integer number (905796741).

Almost surely, 2^1811593481 is an apocalyptic number.

It is an amenable number.

1811593481 is a deficient number, since it is larger than the sum of its proper divisors (1).

1811593481 is an equidigital number, since it uses as much as digits as its factorization.

1811593481 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34560, while the sum is 41.

The square root of 1811593481 is about 42562.8180575488. The cubic root of 1811593481 is about 1219.0464377629.

The spelling of 1811593481 in words is "one billion, eight hundred eleven million, five hundred ninety-three thousand, four hundred eighty-one".