20656678 has 16 divisors (see below), whose sum is σ = 35511840. Its totient is φ = 8827776.

The previous prime is 20656639. The next prime is 20656679. The reversal of 20656678 is 87665602.

It is a super-3 number, since 3×20656678³ (a number of 23 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20656678.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20656679) 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, 3550 + ... + 7342.

It is an arithmetic number, because the mean of its divisors is an integer number (2219490).

Almost surely, 2^20656678 is an apocalyptic number.

20656678 is a deficient number, since it is larger than the sum of its proper divisors (14855162).

20656678 is a wasteful number, since it uses less digits than its factorization.

20656678 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4191.

The product of its (nonzero) digits is 120960, while the sum is 40.

The square root of 20656678 is about 4544.9618260223. The cubic root of 20656678 is about 274.3806579849.

The spelling of 20656678 in words is "twenty million, six hundred fifty-six thousand, six hundred seventy-eight".