20216237 has 2 divisors, whose sum is σ = 20216238. Its totient is φ = 20216236.

The previous prime is 20216221. The next prime is 20216243. The reversal of 20216237 is 73261202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10569001 + 9647236 = 3251^2 + 3106^2 .

It is a cyclic number.

It is not a de Polignac number, because 20216237 - 2⁴ = 20216221 is a prime.

It is a plaindrome in base 16.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20216297) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10108118 + 10108119.

It is an arithmetic number, because the mean of its divisors is an integer number (10108119).

Almost surely, 2^20216237 is an apocalyptic number.

It is an amenable number.

20216237 is a deficient number, since it is larger than the sum of its proper divisors (1).

20216237 is an equidigital number, since it uses as much as digits as its factorization.

20216237 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1008, while the sum is 23.

The square root of 20216237 is about 4496.2469905467. The cubic root of 20216237 is about 272.4165196126.

Adding to 20216237 its reverse (73261202), we get a palindrome (93477439).

The spelling of 20216237 in words is "twenty million, two hundred sixteen thousand, two hundred thirty-seven".