16420121 has 2 divisors, whose sum is σ = 16420122. Its totient is φ = 16420120.

The previous prime is 16420093. The next prime is 16420127. The reversal of 16420121 is 12102461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15721225 + 698896 = 3965^2 + 836^2 .

It is a cyclic number.

It is not a de Polignac number, because 16420121 - 2⁶ = 16420057 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 16420121.

It is not a weakly prime, because it can be changed into another prime (16420127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8210060 + 8210061.

It is an arithmetic number, because the mean of its divisors is an integer number (8210061).

Almost surely, 2^16420121 is an apocalyptic number.

It is an amenable number.

16420121 is a deficient number, since it is larger than the sum of its proper divisors (1).

16420121 is an equidigital number, since it uses as much as digits as its factorization.

16420121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 16420121 is about 4052.1748481525. The cubic root of 16420121 is about 254.1706801241.

Adding to 16420121 its reverse (12102461), we get a palindrome (28522582).

The spelling of 16420121 in words is "sixteen million, four hundred twenty thousand, one hundred twenty-one".