21201106237 has 2 divisors, whose sum is σ = 21201106238. Its totient is φ = 21201106236.

The previous prime is 21201106229. The next prime is 21201106247. The reversal of 21201106237 is 73260110212.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16061506756 + 5139599481 = 126734^2 + 71691^2 .

It is a cyclic number.

It is not a de Polignac number, because 21201106237 - 2³ = 21201106229 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21201106247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10600553118 + 10600553119.

It is an arithmetic number, because the mean of its divisors is an integer number (10600553119).

Almost surely, 2^21201106237 is an apocalyptic number.

It is an amenable number.

21201106237 is a deficient number, since it is larger than the sum of its proper divisors (1).

21201106237 is an equidigital number, since it uses as much as digits as its factorization.

21201106237 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1008, while the sum is 25.

Adding to 21201106237 its reverse (73260110212), we get a palindrome (94461216449).

The spelling of 21201106237 in words is "twenty-one billion, two hundred one million, one hundred six thousand, two hundred thirty-seven".