20685547 has 8 divisors (see below), whose sum is σ = 21890960. Its totient is φ = 19491840.

The previous prime is 20685523. The next prime is 20685551. The reversal of 20685547 is 74558602.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20685547 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20685517) 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, 847 + ... + 6487.

It is an arithmetic number, because the mean of its divisors is an integer number (2736370).

Almost surely, 2^20685547 is an apocalyptic number.

20685547 is a deficient number, since it is larger than the sum of its proper divisors (1205413).

20685547 is a wasteful number, since it uses less digits than its factorization.

20685547 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5853.

The product of its (nonzero) digits is 67200, while the sum is 37.

The square root of 20685547 is about 4548.1366514211. The cubic root of 20685547 is about 274.5084198642.

The spelling of 20685547 in words is "twenty million, six hundred eighty-five thousand, five hundred forty-seven".