1978220 has 12 divisors (see below), whose sum is σ = 4154304. Its totient is φ = 791280.

The previous prime is 1978219. The next prime is 1978267. The reversal of 1978220 is 228791.

It is a happy 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 in 3 ways as a sum of consecutive naturals, for example, 49436 + ... + 49475.

It is an arithmetic number, because the mean of its divisors is an integer number (346192).

2^1978220 is an apocalyptic number.

1978220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1978220 is an abundant number, since it is smaller than the sum of its proper divisors (2176084).

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

1978220 is a wasteful number, since it uses less digits than its factorization.

1978220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98920 (or 98918 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 29.

The square root of 1978220 is about 1406.4920902728. The cubic root of 1978220 is about 125.5330833454.

The spelling of 1978220 in words is "one million, nine hundred seventy-eight thousand, two hundred twenty".