216442901 has 2 divisors, whose sum is σ = 216442902. Its totient is φ = 216442900.

The previous prime is 216442873. The next prime is 216442907. The reversal of 216442901 is 109244612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 189090001 + 27352900 = 13751^2 + 5230^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-216442901 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 (216442907) 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, 108221450 + 108221451.

It is an arithmetic number, because the mean of its divisors is an integer number (108221451).

Almost surely, 2^216442901 is an apocalyptic number.

It is an amenable number.

216442901 is a deficient number, since it is larger than the sum of its proper divisors (1).

216442901 is an equidigital number, since it uses as much as digits as its factorization.

216442901 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 216442901 is about 14711.9985386079. The cubic root of 216442901 is about 600.4098135429.

The spelling of 216442901 in words is "two hundred sixteen million, four hundred forty-two thousand, nine hundred one".