20572438 has 4 divisors (see below), whose sum is σ = 30858660. Its totient is φ = 10286218.

The previous prime is 20572429. The next prime is 20572451. The reversal of 20572438 is 83427502.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 83427502 = 2 ⋅41713751.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

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 as a sum of consecutive naturals, namely, 5143108 + ... + 5143111.

It is an arithmetic number, because the mean of its divisors is an integer number (7714665).

Almost surely, 2^20572438 is an apocalyptic number.

20572438 is a deficient number, since it is larger than the sum of its proper divisors (10286222).

20572438 is a wasteful number, since it uses less digits than its factorization.

20572438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10286221.

The product of its (nonzero) digits is 13440, while the sum is 31.

The square root of 20572438 is about 4535.6849537859. The cubic root of 20572438 is about 274.0071658843.

The spelling of 20572438 in words is "twenty million, five hundred seventy-two thousand, four hundred thirty-eight".