1681145 has 8 divisors (see below), whose sum is σ = 2037960. Its totient is φ = 1331200.

The previous prime is 1681129. The next prime is 1681151. The reversal of 1681145 is 5411861.

It can be written as a sum of positive squares in 4 ways, for example, as 473344 + 1207801 = 688^2 + 1099^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1681145 - 2⁴ = 1681129 is a prime.

It is a super-2 number, since 2×1681145² = 5652497022050, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1160 + ... + 2169.

It is an arithmetic number, because the mean of its divisors is an integer number (254745).

2^1681145 is an apocalyptic number.

It is an amenable number.

1681145 is a deficient number, since it is larger than the sum of its proper divisors (356815).

1681145 is a wasteful number, since it uses less digits than its factorization.

1681145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3435.

The product of its digits is 960, while the sum is 26.

The square root of 1681145 is about 1296.5897577877. The cubic root of 1681145 is about 118.9054400277.

The spelling of 1681145 in words is "one million, six hundred eighty-one thousand, one hundred forty-five".