1966478 has 4 divisors (see below), whose sum is σ = 2949720. Its totient is φ = 983238.

The previous prime is 1966463. The next prime is 1966493. The reversal of 1966478 is 8746691.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8746691 = 59 ⋅148249.

It is an interprime number because it is at equal distance from previous prime (1966463) and next prime (1966493).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 491618 + ... + 491621.

It is an arithmetic number, because the mean of its divisors is an integer number (737430).

2^1966478 is an apocalyptic number.

1966478 is a deficient number, since it is larger than the sum of its proper divisors (983242).

1966478 is an equidigital number, since it uses as much as digits as its factorization.

1966478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 983241.

The product of its digits is 72576, while the sum is 41.

The square root of 1966478 is about 1402.3116629337. The cubic root of 1966478 is about 125.2842172745.

The spelling of 1966478 in words is "one million, nine hundred sixty-six thousand, four hundred seventy-eight".