20656173 has 16 divisors (see below), whose sum is σ = 30697920. Its totient is φ = 12278016.

The previous prime is 20656121. The next prime is 20656183. The reversal of 20656173 is 37165602.

It is not a de Polignac number, because 20656173 - 2¹² = 20652077 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20656173.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20656183) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9690 + ... + 11627.

It is an arithmetic number, because the mean of its divisors is an integer number (1918620).

Almost surely, 2^20656173 is an apocalyptic number.

It is an amenable number.

20656173 is a deficient number, since it is larger than the sum of its proper divisors (10041747).

20656173 is a wasteful number, since it uses less digits than its factorization.

20656173 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21356.

The product of its (nonzero) digits is 7560, while the sum is 30.

The square root of 20656173 is about 4544.9062696606. The cubic root of 20656173 is about 274.3784220113.

The spelling of 20656173 in words is "twenty million, six hundred fifty-six thousand, one hundred seventy-three".