20561168 has 20 divisors (see below), whose sum is σ = 39945360. Its totient is φ = 10252704.

The previous prime is 20561147. The next prime is 20561171. The reversal of 20561168 is 86116502.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 20561168.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5171 + ... + 8237.

It is an arithmetic number, because the mean of its divisors is an integer number (1997268).

Almost surely, 2^20561168 is an apocalyptic number.

It is an amenable number.

20561168 is a deficient number, since it is larger than the sum of its proper divisors (19384192).

20561168 is a wasteful number, since it uses less digits than its factorization.

20561168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3494 (or 3488 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 29.

The square root of 20561168 is about 4534.4424133514. The cubic root of 20561168 is about 273.9571211783.

The spelling of 20561168 in words is "twenty million, five hundred sixty-one thousand, one hundred sixty-eight".