1978145 has 12 divisors (see below), whose sum is σ = 2571516. Its totient is φ = 1460160.

The previous prime is 1978117. The next prime is 1978153. The reversal of 1978145 is 5418791.

It can be written as a sum of positive squares in 6 ways, for example, as 277729 + 1700416 = 527^2 + 1304^2 .

It is a de Polignac number, because none of the positive numbers 2^k-1978145 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 in 11 ways as a sum of consecutive naturals, for example, 326 + ... + 2015.

It is an arithmetic number, because the mean of its divisors is an integer number (214293).

2^1978145 is an apocalyptic number.

It is an amenable number.

1978145 is a deficient number, since it is larger than the sum of its proper divisors (593371).

1978145 is a wasteful number, since it uses less digits than its factorization.

1978145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2372 (or 2359 counting only the distinct ones).

The product of its digits is 10080, while the sum is 35.

The square root of 1978145 is about 1406.4654279434. The cubic root of 1978145 is about 125.5314968855.

The spelling of 1978145 in words is "one million, nine hundred seventy-eight thousand, one hundred forty-five".