21040617 has 8 divisors (see below), whose sum is σ = 30212224. Its totient is φ = 12948048.

The previous prime is 21040601. The next prime is 21040627. The reversal of 21040617 is 71604012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21040617 - 2⁴ = 21040601 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21040593 and 21040602.

It is not an unprimeable number, because it can be changed into a prime (21040627) 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 in 7 ways as a sum of consecutive naturals, for example, 269713 + ... + 269790.

It is an arithmetic number, because the mean of its divisors is an integer number (3776528).

Almost surely, 2^21040617 is an apocalyptic number.

It is an amenable number.

21040617 is a deficient number, since it is larger than the sum of its proper divisors (9171607).

21040617 is a wasteful number, since it uses less digits than its factorization.

21040617 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 539519.

The product of its (nonzero) digits is 336, while the sum is 21.

The square root of 21040617 is about 4587.0052321749. The cubic root of 21040617 is about 276.0701748677.

Adding to 21040617 its reverse (71604012), we get a palindrome (92644629).

The spelling of 21040617 in words is "twenty-one million, forty thousand, six hundred seventeen".