21060517 has 4 divisors (see below), whose sum is σ = 21357216. Its totient is φ = 20763820.

The previous prime is 21060509. The next prime is 21060539. The reversal of 21060517 is 71506012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21060517 - 2³ = 21060509 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21060317) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 148243 + ... + 148384.

It is an arithmetic number, because the mean of its divisors is an integer number (5339304).

Almost surely, 2^21060517 is an apocalyptic number.

It is an amenable number.

21060517 is a deficient number, since it is larger than the sum of its proper divisors (296699).

21060517 is an equidigital number, since it uses as much as digits as its factorization.

21060517 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 296698.

The product of its (nonzero) digits is 420, while the sum is 22.

The square root of 21060517 is about 4589.1738908000. The cubic root of 21060517 is about 276.1571822242.

Adding to 21060517 its reverse (71506012), we get a palindrome (92566529).

The spelling of 21060517 in words is "twenty-one million, sixty thousand, five hundred seventeen".