20353121 has 2 divisors, whose sum is σ = 20353122. Its totient is φ = 20353120.

The previous prime is 20353117. The next prime is 20353153. The reversal of 20353121 is 12135302.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11826721 + 8526400 = 3439^2 + 2920^2 .

It is a cyclic number.

It is not a de Polignac number, because 20353121 - 2² = 20353117 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20353121.

It is not a weakly prime, because it can be changed into another prime (20353721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10176560 + 10176561.

It is an arithmetic number, because the mean of its divisors is an integer number (10176561).

Almost surely, 2^20353121 is an apocalyptic number.

It is an amenable number.

20353121 is a deficient number, since it is larger than the sum of its proper divisors (1).

20353121 is an equidigital number, since it uses as much as digits as its factorization.

20353121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 180, while the sum is 17.

The square root of 20353121 is about 4511.4433388883. The cubic root of 20353121 is about 273.0299805616.

Adding to 20353121 its reverse (12135302), we get a palindrome (32488423).

The spelling of 20353121 in words is "twenty million, three hundred fifty-three thousand, one hundred twenty-one".