1966638 has 16 divisors (see below), whose sum is σ = 4104576. Its totient is φ = 627000.

The previous prime is 1966619. The next prime is 1966663. The reversal of 1966638 is 8366691.

It is a happy number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1966596 and 1966605.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6988 + ... + 7263.

It is an arithmetic number, because the mean of its divisors is an integer number (256536).

2^1966638 is an apocalyptic number.

1966638 is an abundant number, since it is smaller than the sum of its proper divisors (2137938).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1966638 is a wasteful number, since it uses less digits than its factorization.

1966638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14279.

The product of its digits is 46656, while the sum is 39.

The square root of 1966638 is about 1402.3687104325. The cubic root of 1966638 is about 125.2876150464.

The spelling of 1966638 in words is "one million, nine hundred sixty-six thousand, six hundred thirty-eight".