1638628 has 6 divisors (see below), whose sum is σ = 2867606. Its totient is φ = 819312.

The previous prime is 1638599. The next prime is 1638641. The reversal of 1638628 is 8268361.

It can be written as a sum of positive squares in only one way, i.e., 850084 + 788544 = 922^2 + 888^2 .

It is a plaindrome in base 15.

It is a junction number, because it is equal to n+sod(n) for n = 1638593 and 1638602.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 204825 + ... + 204832.

2^1638628 is an apocalyptic number.

It is an amenable number.

1638628 is a deficient number, since it is larger than the sum of its proper divisors (1228978).

1638628 is a wasteful number, since it uses less digits than its factorization.

1638628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 409661 (or 409659 counting only the distinct ones).

The product of its digits is 13824, while the sum is 34.

The square root of 1638628 is about 1280.0890594017. The cubic root of 1638628 is about 117.8944761871.

The spelling of 1638628 in words is "one million, six hundred thirty-eight thousand, six hundred twenty-eight".