1981228 has 6 divisors (see below), whose sum is σ = 3467156. Its totient is φ = 990612.

The previous prime is 1981201. The next prime is 1981237. The reversal of 1981228 is 8221891.

It is a happy number.

It is a super-3 number, since 3×1981228³ = 23330531138630293056, which contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1981228.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 247650 + ... + 247657.

2^1981228 is an apocalyptic number.

It is an amenable number.

1981228 is a deficient number, since it is larger than the sum of its proper divisors (1485928).

1981228 is a wasteful number, since it uses less digits than its factorization.

1981228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 495311 (or 495309 counting only the distinct ones).

The product of its digits is 2304, while the sum is 31.

The square root of 1981228 is about 1407.5610111111. The cubic root of 1981228 is about 125.5966779383.

It can be divided in two parts, 1981 and 228, that added together give a square (2209 = 47²).

The spelling of 1981228 in words is "one million, nine hundred eighty-one thousand, two hundred twenty-eight".