1813003281 has 12 divisors (see below), whose sum is σ = 2679685008. Its totient is φ = 1180560024.

The previous prime is 1813003249. The next prime is 1813003303. The reversal of 1813003281 is 1823003181.

1813003281 is a `hidden beast` number, since 1 + 81 + 300 + 3 + 281 = 666.

It is not a de Polignac number, because 1813003281 - 2⁵ = 1813003249 is a prime.

It is a super-2 number, since 2×1813003281² = 6573961793833529922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1813013281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2341995 + ... + 2342768.

It is an arithmetic number, because the mean of its divisors is an integer number (223307084).

Almost surely, 2^1813003281 is an apocalyptic number.

It is an amenable number.

1813003281 is a deficient number, since it is larger than the sum of its proper divisors (866681727).

1813003281 is a wasteful number, since it uses less digits than its factorization.

1813003281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4684812 (or 4684809 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 1813003281 is about 42579.3762401471. The cubic root of 1813003281 is about 1219.3625804415.

The spelling of 1813003281 in words is "one billion, eight hundred thirteen million, three thousand, two hundred eighty-one".