1671697 has 4 divisors (see below), whose sum is σ = 1716916. Its totient is φ = 1626480.

The previous prime is 1671689. The next prime is 1671707. The reversal of 1671697 is 7961761.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7961761 = 31 ⋅256831.

It can be written as a sum of positive squares in 2 ways, for example, as 732736 + 938961 = 856^2 + 969^2 .

It is a cyclic number.

It is not a de Polignac number, because 1671697 - 2³ = 1671689 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37), and also a Moran number because the ratio is a prime number: 45181 = 1671697 / (1 + 6 + 7 + 1 + 6 + 9 + 7).

It is a Duffinian number.

1671697 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1671097) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22554 + ... + 22627.

It is an arithmetic number, because the mean of its divisors is an integer number (429229).

2^1671697 is an apocalyptic number.

It is an amenable number.

1671697 is a deficient number, since it is larger than the sum of its proper divisors (45219).

1671697 is an equidigital number, since it uses as much as digits as its factorization.

1671697 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45218.

The product of its digits is 15876, while the sum is 37.

The square root of 1671697 is about 1292.9412206284. The cubic root of 1671697 is about 118.6822727375.

Subtracting 1671697 from its reverse (7961761), we obtain a square (6290064 = 2508²).

The spelling of 1671697 in words is "one million, six hundred seventy-one thousand, six hundred ninety-seven".