1981304 has 16 divisors (see below), whose sum is σ = 4000920. Its totient is φ = 914400.

The previous prime is 1981297. The next prime is 1981337. The reversal of 1981304 is 4031891.

It is a super-3 number, since 3×1981304³ = 23333216122465147392, which contains 333 as substring.

It is a Smith number, since the sum of its digits (26) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (26).

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 in 3 ways as a sum of consecutive naturals, for example, 9422 + ... + 9629.

2^1981304 is an apocalyptic number.

It is an amenable number.

1981304 is an abundant number, since it is smaller than the sum of its proper divisors (2019616).

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

1981304 is a wasteful number, since it uses less digits than its factorization.

1981304 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19070 (or 19066 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 1981304 is about 1407.5880079057. The cubic root of 1981304 is about 125.5982838826.

The spelling of 1981304 in words is "one million, nine hundred eighty-one thousand, three hundred four".