1966138 has 4 divisors (see below), whose sum is σ = 2949210. Its totient is φ = 983068.

The previous prime is 1966127. The next prime is 1966163. The reversal of 1966138 is 8316691.

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

It can be written as a sum of positive squares in only one way, i.e., 1760929 + 205209 = 1327^2 + 453^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 491533 + ... + 491536.

2^1966138 is an apocalyptic number.

1966138 is a deficient number, since it is larger than the sum of its proper divisors (983072).

1966138 is an equidigital number, since it uses as much as digits as its factorization.

1966138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 983071.

The product of its digits is 7776, while the sum is 34.

The square root of 1966138 is about 1402.1904292927. The cubic root of 1966138 is about 125.2769963972.

The spelling of 1966138 in words is "one million, nine hundred sixty-six thousand, one hundred thirty-eight".