1638123 has 16 divisors (see below), whose sum is σ = 2380800. Its totient is φ = 997920.

The previous prime is 1638121. The next prime is 1638127. The reversal of 1638123 is 3218361.

It is not a de Polignac number, because 1638123 - 2¹ = 1638121 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a junction number, because it is equal to n+sod(n) for n = 1638093 and 1638102.

It is not an unprimeable number, because it can be changed into a prime (1638121) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1158 + ... + 2148.

It is an arithmetic number, because the mean of its divisors is an integer number (148800).

2^1638123 is an apocalyptic number.

1638123 is a deficient number, since it is larger than the sum of its proper divisors (742677).

1638123 is a wasteful number, since it uses less digits than its factorization.

1638123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1042.

The product of its digits is 864, while the sum is 24.

The square root of 1638123 is about 1279.8917923012. The cubic root of 1638123 is about 117.8823638534.

The spelling of 1638123 in words is "one million, six hundred thirty-eight thousand, one hundred twenty-three".