21136441 has 2 divisors, whose sum is σ = 21136442. Its totient is φ = 21136440.

The previous prime is 21136433. The next prime is 21136463. The reversal of 21136441 is 14463112.

It is an a-pointer prime, because the next prime (21136463) can be obtained adding 21136441 to its sum of digits (22).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21123216 + 13225 = 4596^2 + 115^2 .

It is a cyclic number.

It is not a de Polignac number, because 21136441 - 2³ = 21136433 is a prime.

It is not a weakly prime, because it can be changed into another prime (21136481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10568220 + 10568221.

It is an arithmetic number, because the mean of its divisors is an integer number (10568221).

Almost surely, 2^21136441 is an apocalyptic number.

It is an amenable number.

21136441 is a deficient number, since it is larger than the sum of its proper divisors (1).

21136441 is an equidigital number, since it uses as much as digits as its factorization.

21136441 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 576, while the sum is 22.

The square root of 21136441 is about 4597.4385259620. The cubic root of 21136441 is about 276.4886367761.

Adding to 21136441 its reverse (14463112), we get a palindrome (35599553).

The spelling of 21136441 in words is "twenty-one million, one hundred thirty-six thousand, four hundred forty-one".