1681669 has 4 divisors (see below), whose sum is σ = 1834560. Its totient is φ = 1528780.

The previous prime is 1681661. The next prime is 1681679. The reversal of 1681669 is 9661861.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1681669 - 2³ = 1681661 is a prime.

It is a super-3 number, since 3×1681669³ = 14267333402029623927, which contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1681661) 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, 76429 + ... + 76450.

It is an arithmetic number, because the mean of its divisors is an integer number (458640).

2^1681669 is an apocalyptic number.

It is an amenable number.

1681669 is a deficient number, since it is larger than the sum of its proper divisors (152891).

1681669 is a wasteful number, since it uses less digits than its factorization.

1681669 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152890.

The product of its digits is 15552, while the sum is 37.

The square root of 1681669 is about 1296.7918105849. The cubic root of 1681669 is about 118.9177927156.

The spelling of 1681669 in words is "one million, six hundred eighty-one thousand, six hundred sixty-nine".