1978118 has 4 divisors (see below), whose sum is σ = 2967180. Its totient is φ = 989058.

The previous prime is 1978117. The next prime is 1978153. The reversal of 1978118 is 8118791.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1978111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 494528 + ... + 494531.

It is an arithmetic number, because the mean of its divisors is an integer number (741795).

2^1978118 is an apocalyptic number.

1978118 is a deficient number, since it is larger than the sum of its proper divisors (989062).

1978118 is an equidigital number, since it uses as much as digits as its factorization.

1978118 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 989061.

The product of its digits is 4032, while the sum is 35.

The square root of 1978118 is about 1406.4558293811. The cubic root of 1978118 is about 125.5309257501.

The spelling of 1978118 in words is "one million, nine hundred seventy-eight thousand, one hundred eighteen".