20685499 has 8 divisors (see below), whose sum is σ = 21418560. Its totient is φ = 19964736.

The previous prime is 20685473. The next prime is 20685503. The reversal of 20685499 is 99458602.

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

It is a cyclic number.

It is not a de Polignac number, because 20685499 - 2¹⁷ = 20554427 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20685449) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 417 + ... + 6445.

It is an arithmetic number, because the mean of its divisors is an integer number (2677320).

Almost surely, 2^20685499 is an apocalyptic number.

20685499 is a deficient number, since it is larger than the sum of its proper divisors (733061).

20685499 is an equidigital number, since it uses as much as digits as its factorization.

20685499 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6149.

The product of its (nonzero) digits is 155520, while the sum is 43.

The square root of 20685499 is about 4548.1313745317. The cubic root of 20685499 is about 274.5082075354.

The spelling of 20685499 in words is "twenty million, six hundred eighty-five thousand, four hundred ninety-nine".