19981133 has 8 divisors (see below), whose sum is σ = 20309016. Its totient is φ = 19656000.

The previous prime is 19981109. The next prime is 19981139. The reversal of 19981133 is 33118991.

It can be written as a sum of positive squares in 4 ways, for example, as 7856809 + 12124324 = 2803^2 + 3482^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 19981133 - 2¹⁸ = 19718989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 19981093 and 19981102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19981139) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17735 + ... + 18827.

It is an arithmetic number, because the mean of its divisors is an integer number (2538627).

Almost surely, 2^19981133 is an apocalyptic number.

It is an amenable number.

19981133 is a deficient number, since it is larger than the sum of its proper divisors (327883).

19981133 is a wasteful number, since it uses less digits than its factorization.

19981133 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1375.

The product of its digits is 5832, while the sum is 35.

The square root of 19981133 is about 4470.0260625638. The cubic root of 19981133 is about 271.3563799436.

The spelling of 19981133 in words is "nineteen million, nine hundred eighty-one thousand, one hundred thirty-three".