19690729 has 4 divisors (see below), whose sum is σ = 19701376. Its totient is φ = 19680084.

The previous prime is 19690721. The next prime is 19690733. The reversal of 19690729 is 92709691.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 92709691 = 61 ⋅1519831.

It is a cyclic number.

It is not a de Polignac number, because 19690729 - 2³ = 19690721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19690721) by changing a digit.

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, 1749 + ... + 6514.

It is an arithmetic number, because the mean of its divisors is an integer number (4925344).

Almost surely, 2^19690729 is an apocalyptic number.

It is an amenable number.

19690729 is a deficient number, since it is larger than the sum of its proper divisors (10647).

19690729 is an equidigital number, since it uses as much as digits as its factorization.

19690729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10646.

The product of its (nonzero) digits is 61236, while the sum is 43.

The square root of 19690729 is about 4437.4236894847. The cubic root of 19690729 is about 270.0353360245.

The spelling of 19690729 in words is "nineteen million, six hundred ninety thousand, seven hundred twenty-nine".