16201121 has 2 divisors, whose sum is σ = 16201122. Its totient is φ = 16201120.

The previous prime is 16201117. The next prime is 16201123. The reversal of 16201121 is 12110261.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13432225 + 2768896 = 3665^2 + 1664^2 .

It is an emirp because it is prime and its reverse (12110261) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16201121 - 2² = 16201117 is a prime.

Together with 16201123, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 16201096 and 16201105.

It is not a weakly prime, because it can be changed into another prime (16201123) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8100560 + 8100561.

It is an arithmetic number, because the mean of its divisors is an integer number (8100561).

Almost surely, 2^16201121 is an apocalyptic number.

It is an amenable number.

16201121 is a deficient number, since it is larger than the sum of its proper divisors (1).

16201121 is an equidigital number, since it uses as much as digits as its factorization.

16201121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24, while the sum is 14.

The square root of 16201121 is about 4025.0616144352. The cubic root of 16201121 is about 253.0356358017.

Adding to 16201121 its reverse (12110261), we get a palindrome (28311382).

The spelling of 16201121 in words is "sixteen million, two hundred one thousand, one hundred twenty-one".