1664637 has 8 divisors (see below), whose sum is σ = 2390304. Its totient is φ = 1024368.

The previous prime is 1664633. The next prime is 1664651. The reversal of 1664637 is 7364661.

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

It is not a de Polignac number, because 1664637 - 2² = 1664633 is a prime.

1664637 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 1664598 and 1664607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1664633) by changing a digit.

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, 21303 + ... + 21380.

It is an arithmetic number, because the mean of its divisors is an integer number (298788).

2^1664637 is an apocalyptic number.

It is an amenable number.

1664637 is a deficient number, since it is larger than the sum of its proper divisors (725667).

1664637 is a wasteful number, since it uses less digits than its factorization.

1664637 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42699.

The product of its digits is 18144, while the sum is 33.

The square root of 1664637 is about 1290.2081227461. The cubic root of 1664637 is about 118.5149618809.

The spelling of 1664637 in words is "one million, six hundred sixty-four thousand, six hundred thirty-seven".