1978142 has 4 divisors (see below), whose sum is σ = 2967216. Its totient is φ = 989070.

The previous prime is 1978117. The next prime is 1978153. The reversal of 1978142 is 2418791.

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

It is a junction number, because it is equal to n+sod(n) for n = 1978099 and 1978108.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 494534 + ... + 494537.

It is an arithmetic number, because the mean of its divisors is an integer number (741804).

2^1978142 is an apocalyptic number.

1978142 is a deficient number, since it is larger than the sum of its proper divisors (989074).

1978142 is an equidigital number, since it uses as much as digits as its factorization.

1978142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 989073.

The product of its digits is 4032, while the sum is 32.

The square root of 1978142 is about 1406.4643614397. The cubic root of 1978142 is about 125.5314334262.

The spelling of 1978142 in words is "one million, nine hundred seventy-eight thousand, one hundred forty-two".