20685637 has 8 divisors (see below), whose sum is σ = 23974272. Its totient is φ = 17480400.

The previous prime is 20685631. The next prime is 20685653. The reversal of 20685637 is 73658602.

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

It is not a de Polignac number, because 20685637 - 2³ = 20685629 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20685596 and 20685605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20685631) by changing a digit.

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 in 7 ways as a sum of consecutive naturals, for example, 20314 + ... + 21307.

It is an arithmetic number, because the mean of its divisors is an integer number (2996784).

Almost surely, 2^20685637 is an apocalyptic number.

It is an amenable number.

20685637 is a deficient number, since it is larger than the sum of its proper divisors (3288635).

20685637 is an equidigital number, since it uses as much as digits as its factorization.

20685637 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41699.

The product of its (nonzero) digits is 60480, while the sum is 37.

The square root of 20685637 is about 4548.1465455722. The cubic root of 20685637 is about 274.5088179799.

The spelling of 20685637 in words is "twenty million, six hundred eighty-five thousand, six hundred thirty-seven".