1689971 has 4 divisors (see below), whose sum is σ = 1763472. Its totient is φ = 1616472.

The previous prime is 1689967. The next prime is 1690009. The reversal of 1689971 is 1799861.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1799861 = 7 ⋅257123.

It is a cyclic number.

It is not a de Polignac number, because 1689971 - 2² = 1689967 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1689911) 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, 36716 + ... + 36761.

It is an arithmetic number, because the mean of its divisors is an integer number (440868).

2^1689971 is an apocalyptic number.

1689971 is a deficient number, since it is larger than the sum of its proper divisors (73501).

1689971 is an equidigital number, since it uses as much as digits as its factorization.

1689971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73500.

The product of its digits is 27216, while the sum is 41.

The square root of 1689971 is about 1299.9888461060. The cubic root of 1689971 is about 119.1131611940.

The spelling of 1689971 in words is "one million, six hundred eighty-nine thousand, nine hundred seventy-one".