21106037 has 2 divisors, whose sum is σ = 21106038. Its totient is φ = 21106036.

The previous prime is 21105977. The next prime is 21106049. The reversal of 21106037 is 73060112.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16048036 + 5058001 = 4006^2 + 2249^2 .

It is a cyclic number.

It is not a de Polignac number, because 21106037 - 2⁸ = 21105781 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 (21106067) 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, 10553018 + 10553019.

It is an arithmetic number, because the mean of its divisors is an integer number (10553019).

Almost surely, 2^21106037 is an apocalyptic number.

It is an amenable number.

21106037 is a deficient number, since it is larger than the sum of its proper divisors (1).

21106037 is an equidigital number, since it uses as much as digits as its factorization.

21106037 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 252, while the sum is 20.

The square root of 21106037 is about 4594.1307121152. The cubic root of 21106037 is about 276.3560002159.

Adding to 21106037 its reverse (73060112), we get a palindrome (94166149).

The spelling of 21106037 in words is "twenty-one million, one hundred six thousand, thirty-seven".