19987429 has 8 divisors (see below), whose sum is σ = 24919488. Its totient is φ = 15574560.

The previous prime is 19987403. The next prime is 19987433. The reversal of 19987429 is 92478991.

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 19987429 - 2⁷ = 19987301 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19987469) 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, 129712 + ... + 129865.

It is an arithmetic number, because the mean of its divisors is an integer number (3114936).

Almost surely, 2^19987429 is an apocalyptic number.

It is an amenable number.

19987429 is a deficient number, since it is larger than the sum of its proper divisors (4932059).

19987429 is a wasteful number, since it uses less digits than its factorization.

19987429 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 259595.

The product of its digits is 326592, while the sum is 49.

The square root of 19987429 is about 4470.7302535492. The cubic root of 19987429 is about 271.3848781667.

The spelling of 19987429 in words is "nineteen million, nine hundred eighty-seven thousand, four hundred twenty-nine".