1978424 has 40 divisors (see below), whose sum is σ = 4369560. Its totient is φ = 839664.

The previous prime is 1978423. The next prime is 1978429. The reversal of 1978424 is 4248791.

Its product of digits (16128) is a multiple of the sum of its prime divisors (112).

It is a zygodrome in base 2 and base 7.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1978421) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 19157 + ... + 19259.

It is an arithmetic number, because the mean of its divisors is an integer number (109239).

2^1978424 is an apocalyptic number.

1978424 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1978424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2184780).

1978424 is an abundant number, since it is smaller than the sum of its proper divisors (2391136).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1978424 is an equidigital number, since it uses as much as digits as its factorization.

1978424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137 (or 112 counting only the distinct ones).

The product of its digits is 16128, while the sum is 35.

The square root of 1978424 is about 1406.5646092519. The cubic root of 1978424 is about 125.5373983135.

The spelling of 1978424 in words is "one million, nine hundred seventy-eight thousand, four hundred twenty-four".