21310937 has 2 divisors, whose sum is σ = 21310938. Its totient is φ = 21310936.

The previous prime is 21310921. The next prime is 21310957. The reversal of 21310937 is 73901312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21307456 + 3481 = 4616^2 + 59^2 .

It is a cyclic number.

It is not a de Polignac number, because 21310937 - 2⁴ = 21310921 is a prime.

It is not a weakly prime, because it can be changed into another prime (21310957) 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, 10655468 + 10655469.

It is an arithmetic number, because the mean of its divisors is an integer number (10655469).

Almost surely, 2^21310937 is an apocalyptic number.

It is an amenable number.

21310937 is a deficient number, since it is larger than the sum of its proper divisors (1).

21310937 is an equidigital number, since it uses as much as digits as its factorization.

21310937 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1134, while the sum is 26.

The square root of 21310937 is about 4616.3770426602. The cubic root of 21310937 is about 277.2474210680.

The spelling of 21310937 in words is "twenty-one million, three hundred ten thousand, nine hundred thirty-seven".