20928219 has 8 divisors (see below), whose sum is σ = 30050832. Its totient is φ = 12878880.

The previous prime is 20928217. The next prime is 20928223. The reversal of 20928219 is 91282902.

It is a happy number.

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

It is not a de Polignac number, because 20928219 - 2¹ = 20928217 is a prime.

It is a super-2 number, since 2×20928219² = 875980701023922, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20928219.

It is not an unprimeable number, because it can be changed into a prime (20928217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 268272 + ... + 268349.

It is an arithmetic number, because the mean of its divisors is an integer number (3756354).

Almost surely, 2^20928219 is an apocalyptic number.

20928219 is a deficient number, since it is larger than the sum of its proper divisors (9122613).

20928219 is a wasteful number, since it uses less digits than its factorization.

20928219 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 536637.

The product of its (nonzero) digits is 5184, while the sum is 33.

The square root of 20928219 is about 4574.7370416233. The cubic root of 20928219 is about 275.5777122304.

The spelling of 20928219 in words is "twenty million, nine hundred twenty-eight thousand, two hundred nineteen".