21700717 has 8 divisors (see below), whose sum is σ = 22955360. Its totient is φ = 20457360.

The previous prime is 21700711. The next prime is 21700741. The reversal of 21700717 is 71700712.

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

It is a cyclic number.

It is not a de Polignac number, because 21700717 - 2³ = 21700709 is a prime.

It is a super-2 number, since 2×21700717² = 941842236628178, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21700691 and 21700700.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21700711) 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, 1303 + ... + 6715.

It is an arithmetic number, because the mean of its divisors is an integer number (2869420).

Almost surely, 2^21700717 is an apocalyptic number.

It is an amenable number.

21700717 is a deficient number, since it is larger than the sum of its proper divisors (1254643).

21700717 is a wasteful number, since it uses less digits than its factorization.

21700717 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5643.

The product of its (nonzero) digits is 686, while the sum is 25.

The square root of 21700717 is about 4658.4028378834. The cubic root of 21700717 is about 278.9275172167.

The spelling of 21700717 in words is "twenty-one million, seven hundred thousand, seven hundred seventeen".