20023121 has 2 divisors, whose sum is σ = 20023122. Its totient is φ = 20023120.

The previous prime is 20023063. The next prime is 20023139. The reversal of 20023121 is 12132002.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12673600 + 7349521 = 3560^2 + 2711^2 .

It is a cyclic number.

It is not a de Polignac number, because 20023121 - 2⁶ = 20023057 is a prime.

It is a super-3 number, since 3×20023121³ (a number of 23 digits) contains 333 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20023141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10011560 + 10011561.

It is an arithmetic number, because the mean of its divisors is an integer number (10011561).

Almost surely, 2^20023121 is an apocalyptic number.

It is an amenable number.

20023121 is a deficient number, since it is larger than the sum of its proper divisors (1).

20023121 is an equidigital number, since it uses as much as digits as its factorization.

20023121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 20023121 is about 4474.7202147173. The cubic root of 20023121 is about 271.5463214606.

Adding to 20023121 its reverse (12132002), we get a palindrome (32155123).

The spelling of 20023121 in words is "twenty million, twenty-three thousand, one hundred twenty-one".