21131137 has 2 divisors, whose sum is σ = 21131138. Its totient is φ = 21131136.

The previous prime is 21131087. The next prime is 21131141. The reversal of 21131137 is 73113112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21123216 + 7921 = 4596^2 + 89^2 .

It is a cyclic number.

It is not a de Polignac number, because 21131137 - 2⁷ = 21131009 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21131147) 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, 10565568 + 10565569.

It is an arithmetic number, because the mean of its divisors is an integer number (10565569).

Almost surely, 2^21131137 is an apocalyptic number.

It is an amenable number.

21131137 is a deficient number, since it is larger than the sum of its proper divisors (1).

21131137 is an equidigital number, since it uses as much as digits as its factorization.

21131137 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 126, while the sum is 19.

The square root of 21131137 is about 4596.8616468195. The cubic root of 21131137 is about 276.4655073947.

Adding to 21131137 its reverse (73113112), we get a palindrome (94244249).

The spelling of 21131137 in words is "twenty-one million, one hundred thirty-one thousand, one hundred thirty-seven".