20685438 has 12 divisors (see below), whose sum is σ = 44818488. Its totient is φ = 6895140.

The previous prime is 20685421. The next prime is 20685449. The reversal of 20685438 is 83458602.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 574578 + ... + 574613.

It is an arithmetic number, because the mean of its divisors is an integer number (3734874).

Almost surely, 2^20685438 is an apocalyptic number.

20685438 is an abundant number, since it is smaller than the sum of its proper divisors (24133050).

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

20685438 is a wasteful number, since it uses less digits than its factorization.

20685438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1149199 (or 1149196 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

The square root of 20685438 is about 4548.1246684760. The cubic root of 20685438 is about 274.5079377003.

The spelling of 20685438 in words is "twenty million, six hundred eighty-five thousand, four hundred thirty-eight".