20129438 has 8 divisors (see below), whose sum is σ = 34507632. Its totient is φ = 8626896.

The previous prime is 20129429. The next prime is 20129471. The reversal of 20129438 is 83492102.

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

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20129438.

It is a congruent number.

It is an unprimeable number.

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, 718895 + ... + 718922.

It is an arithmetic number, because the mean of its divisors is an integer number (4313454).

Almost surely, 2^20129438 is an apocalyptic number.

20129438 is a deficient number, since it is larger than the sum of its proper divisors (14378194).

20129438 is a wasteful number, since it uses less digits than its factorization.

20129438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1437826.

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 20129438 is about 4486.5842241064. The cubic root of 20129438 is about 272.0260842200.

The spelling of 20129438 in words is "twenty million, one hundred twenty-nine thousand, four hundred thirty-eight".