1638974 has 4 divisors (see below), whose sum is σ = 2458464. Its totient is φ = 819486.

The previous prime is 1638947. The next prime is 1638977. The reversal of 1638974 is 4798361.

It is a semiprime because it is the product of two primes.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1638977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 409742 + ... + 409745.

It is an arithmetic number, because the mean of its divisors is an integer number (614616).

2^1638974 is an apocalyptic number.

1638974 is a deficient number, since it is larger than the sum of its proper divisors (819490).

1638974 is an equidigital number, since it uses as much as digits as its factorization.

1638974 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 819489.

The product of its digits is 36288, while the sum is 38.

The square root of 1638974 is about 1280.2241991151. The cubic root of 1638974 is about 117.9027734980.

The spelling of 1638974 in words is "one million, six hundred thirty-eight thousand, nine hundred seventy-four".