20688219 has 6 divisors (see below), whose sum is σ = 29882996. Its totient is φ = 13792140.

The previous prime is 20688209. The next prime is 20688251. The reversal of 20688219 is 91288602.

It is not a de Polignac number, because 20688219 - 2⁹ = 20687707 is a prime.

It is a super-2 number, since 2×20688219² = 856004810783922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20688209) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1149337 + ... + 1149354.

Almost surely, 2^20688219 is an apocalyptic number.

20688219 is a deficient number, since it is larger than the sum of its proper divisors (9194777).

20688219 is a wasteful number, since it uses less digits than its factorization.

20688219 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2298697 (or 2298694 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 20688219 is about 4548.4303886066. The cubic root of 20688219 is about 274.5202389847.

The spelling of 20688219 in words is "twenty million, six hundred eighty-eight thousand, two hundred nineteen".