20561368 has 16 divisors (see below), whose sum is σ = 38810160. Its totient is φ = 10212000.

The previous prime is 20561351. The next prime is 20561369. The reversal of 20561368 is 86316502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20561369) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7303 + ... + 9718.

It is an arithmetic number, because the mean of its divisors is an integer number (2425635).

Almost surely, 2^20561368 is an apocalyptic number.

It is an amenable number.

20561368 is a deficient number, since it is larger than the sum of its proper divisors (18248792).

20561368 is a wasteful number, since it uses less digits than its factorization.

20561368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17178 (or 17174 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 20561368 is about 4534.4644667259. The cubic root of 20561368 is about 273.9580094425.

The spelling of 20561368 in words is "twenty million, five hundred sixty-one thousand, three hundred sixty-eight".