19999829 has 4 divisors (see below), whose sum is σ = 20026476. Its totient is φ = 19973184.

The previous prime is 19999817. The next prime is 19999831. The reversal of 19999829 is 92899991.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4774225 + 15225604 = 2185^2 + 3902^2 .

It is a cyclic number.

It is not a de Polignac number, because 19999829 - 2¹⁶ = 19934293 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19999729) 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 3 ways as a sum of consecutive naturals, for example, 12164 + ... + 13709.

It is an arithmetic number, because the mean of its divisors is an integer number (5006619).

Almost surely, 2^19999829 is an apocalyptic number.

It is an amenable number.

19999829 is a deficient number, since it is larger than the sum of its proper divisors (26647).

19999829 is an equidigital number, since it uses as much as digits as its factorization.

19999829 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26646.

The product of its digits is 944784, while the sum is 56.

The square root of 19999829 is about 4472.1168365775. The cubic root of 19999829 is about 271.4409880483.

It can be divided in two parts, 1999982 and 9, that added together give a palindrome (1999991).

The spelling of 19999829 in words is "nineteen million, nine hundred ninety-nine thousand, eight hundred twenty-nine".