19826981 has 16 divisors (see below), whose sum is σ = 21954240. Its totient is φ = 17821440.

The previous prime is 19826971. The next prime is 19827023. The reversal of 19826981 is 18962891.

It is not a de Polignac number, because 19826981 - 2¹⁸ = 19564837 is a prime.

It is a super-2 number, since 2×19826981² = 786218351148722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19826971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 64430 + ... + 64736.

It is an arithmetic number, because the mean of its divisors is an integer number (1372140).

Almost surely, 2^19826981 is an apocalyptic number.

It is an amenable number.

19826981 is a deficient number, since it is larger than the sum of its proper divisors (2127259).

19826981 is a wasteful number, since it uses less digits than its factorization.

19826981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 484.

The product of its digits is 62208, while the sum is 44.

The square root of 19826981 is about 4452.7498245466. The cubic root of 19826981 is about 270.6567505555.

The spelling of 19826981 in words is "nineteen million, eight hundred twenty-six thousand, nine hundred eighty-one".