1681820153 has 24 divisors (see below), whose sum is σ = 1891116864. Its totient is φ = 1486645920.

The previous prime is 1681820141. The next prime is 1681820167. The reversal of 1681820153 is 3510281861.

It is not a de Polignac number, because 1681820153 - 2⁴ = 1681820137 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1681820453) 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 in 23 ways as a sum of consecutive naturals, for example, 1286126 + ... + 1287432.

It is an arithmetic number, because the mean of its divisors is an integer number (78796536).

Almost surely, 2^1681820153 is an apocalyptic number.

1681820153 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

1681820153 is a deficient number, since it is larger than the sum of its proper divisors (209296711).

1681820153 is a wasteful number, since it uses less digits than its factorization.

1681820153 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1485 (or 1454 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 35.

The square root of 1681820153 is about 41010.0006461839. Note that the first 3 decimals coincide. The cubic root of 1681820153 is about 1189.2135549411.

The spelling of 1681820153 in words is "one billion, six hundred eighty-one million, eight hundred twenty thousand, one hundred fifty-three".