1980638 has 16 divisors (see below), whose sum is σ = 3264624. Its totient is φ = 893760.

The previous prime is 1980637. The next prime is 1980659. The reversal of 1980638 is 8360891.

It is a junction number, because it is equal to n+sod(n) for n = 1980598 and 1980607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1980631) 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, 4106 + ... + 4562.

It is an arithmetic number, because the mean of its divisors is an integer number (204039).

2^1980638 is an apocalyptic number.

1980638 is a deficient number, since it is larger than the sum of its proper divisors (1283986).

1980638 is a wasteful number, since it uses less digits than its factorization.

1980638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 667.

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 1980638 is about 1407.3514131161. The cubic root of 1980638 is about 125.5842093419.

The spelling of 1980638 in words is "one million, nine hundred eighty thousand, six hundred thirty-eight".