20720163 has 8 divisors (see below), whose sum is σ = 27648000. Its totient is φ = 13802888.

The previous prime is 20720153. The next prime is 20720209. The reversal of 20720163 is 36102702.

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 not a de Polignac number, because 20720163 - 2⁵ = 20720131 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20720113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5758 + ... + 8636.

It is an arithmetic number, because the mean of its divisors is an integer number (3456000).

Almost surely, 2^20720163 is an apocalyptic number.

20720163 is a deficient number, since it is larger than the sum of its proper divisors (6927837).

20720163 is a wasteful number, since it uses less digits than its factorization.

20720163 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5281.

The product of its (nonzero) digits is 504, while the sum is 21.

The square root of 20720163 is about 4551.9405751833. The cubic root of 20720163 is about 274.6614588892.

Adding to 20720163 its reverse (36102702), we get a palindrome (56822865).

The spelling of 20720163 in words is "twenty million, seven hundred twenty thousand, one hundred sixty-three".