1681503 has 4 divisors (see below), whose sum is σ = 2242008. Its totient is φ = 1121000.

The previous prime is 1681501. The next prime is 1681513. The reversal of 1681503 is 3051861.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1681503 - 2¹ = 1681501 is a prime.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1681501) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 280248 + ... + 280253.

It is an arithmetic number, because the mean of its divisors is an integer number (560502).

2^1681503 is an apocalyptic number.

1681503 is a deficient number, since it is larger than the sum of its proper divisors (560505).

1681503 is an equidigital number, since it uses as much as digits as its factorization.

1681503 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 560504.

The product of its (nonzero) digits is 720, while the sum is 24.

The square root of 1681503 is about 1296.7278048997. The cubic root of 1681503 is about 118.9138797372.

The spelling of 1681503 in words is "one million, six hundred eighty-one thousand, five hundred three".