20158638 has 8 divisors (see below), whose sum is σ = 40317288. Its totient is φ = 6719544.

The previous prime is 20158627. The next prime is 20158661. The reversal of 20158638 is 83685102.

It is a happy number.

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

20158638 is an admirable number.

It is a junction number, because it is equal to n+sod(n) for n = 20158599 and 20158608.

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, 1679881 + ... + 1679892.

It is an arithmetic number, because the mean of its divisors is an integer number (5039661).

Almost surely, 2^20158638 is an apocalyptic number.

20158638 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20158638 is a wasteful number, since it uses less digits than its factorization.

20158638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3359778.

The product of its (nonzero) digits is 11520, while the sum is 33.

The square root of 20158638 is about 4489.8371908122. The cubic root of 20158638 is about 272.1575554171.

The spelling of 20158638 in words is "twenty million, one hundred fifty-eight thousand, six hundred thirty-eight".