21041513 has 2 divisors, whose sum is σ = 21041514. Its totient is φ = 21041512.

The previous prime is 21041479. The next prime is 21041519. The reversal of 21041513 is 31514012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14348944 + 6692569 = 3788^2 + 2587^2 .

It is a cyclic number.

It is not a de Polignac number, because 21041513 - 2¹⁰ = 21040489 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21041491 and 21041500.

It is not a weakly prime, because it can be changed into another prime (21041519) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10520756 + 10520757.

It is an arithmetic number, because the mean of its divisors is an integer number (10520757).

Almost surely, 2^21041513 is an apocalyptic number.

It is an amenable number.

21041513 is a deficient number, since it is larger than the sum of its proper divisors (1).

21041513 is an equidigital number, since it uses as much as digits as its factorization.

21041513 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 21041513 is about 4587.1028983444. The cubic root of 21041513 is about 276.0740935640.

Adding to 21041513 its reverse (31514012), we get a palindrome (52555525).

The spelling of 21041513 in words is "twenty-one million, forty-one thousand, five hundred thirteen".