216016421 has 2 divisors, whose sum is σ = 216016422. Its totient is φ = 216016420.

The previous prime is 216016369. The next prime is 216016469. The reversal of 216016421 is 124610612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 214300321 + 1716100 = 14639^2 + 1310^2 .

It is a cyclic number.

It is not a de Polignac number, because 216016421 - 2⁶ = 216016357 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216016121) 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, 108008210 + 108008211.

It is an arithmetic number, because the mean of its divisors is an integer number (108008211).

Almost surely, 2^216016421 is an apocalyptic number.

It is an amenable number.

216016421 is a deficient number, since it is larger than the sum of its proper divisors (1).

216016421 is an equidigital number, since it uses as much as digits as its factorization.

216016421 is an odious number, because the sum of its binary digits is odd.

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

The square root of 216016421 is about 14697.4970998466. The cubic root of 216016421 is about 600.0152042443.

It can be divided in two parts, 2160 and 16421, that added together give a palindrome (18581).

The spelling of 216016421 in words is "two hundred sixteen million, sixteen thousand, four hundred twenty-one".