216021349 has 2 divisors, whose sum is σ = 216021350. Its totient is φ = 216021348.

The previous prime is 216021343. The next prime is 216021367. The reversal of 216021349 is 943120612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 213364449 + 2656900 = 14607^2 + 1630^2 .

It is a cyclic number.

It is not a de Polignac number, because 216021349 - 2³ = 216021341 is a prime.

It is equal to p_11915524 and since 216021349 and 11915524 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216021341) 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, 108010674 + 108010675.

It is an arithmetic number, because the mean of its divisors is an integer number (108010675).

Almost surely, 2^216021349 is an apocalyptic number.

It is an amenable number.

216021349 is a deficient number, since it is larger than the sum of its proper divisors (1).

216021349 is an equidigital number, since it uses as much as digits as its factorization.

216021349 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 216021349 is about 14697.6647464827. The cubic root of 216021349 is about 600.0197669414.

The spelling of 216021349 in words is "two hundred sixteen million, twenty-one thousand, three hundred forty-nine".