20863121 has 8 divisors (see below), whose sum is σ = 22080000. Its totient is φ = 19658160.

The previous prime is 20863111. The next prime is 20863123. The reversal of 20863121 is 12136802.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20863121 - 2¹⁰ = 20862097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20863123) 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, 755 + ... + 6503.

It is an arithmetic number, because the mean of its divisors is an integer number (2760000).

Almost surely, 2^20863121 is an apocalyptic number.

It is an amenable number.

20863121 is a deficient number, since it is larger than the sum of its proper divisors (1216879).

20863121 is a wasteful number, since it uses less digits than its factorization.

20863121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5959.

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 20863121 is about 4567.6165557104. The cubic root of 20863121 is about 275.2916838991.

Adding to 20863121 its reverse (12136802), we get a palindrome (32999923).

The spelling of 20863121 in words is "twenty million, eight hundred sixty-three thousand, one hundred twenty-one".