20980217 has 4 divisors (see below), whose sum is σ = 21005556. Its totient is φ = 20954880.

The previous prime is 20980213. The next prime is 20980231. The reversal of 20980217 is 71208902.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 71208902 = 2 ⋅35604451.

It can be written as a sum of positive squares in 2 ways, for example, as 8667136 + 12313081 = 2944^2 + 3509^2 .

It is a cyclic number.

It is not a de Polignac number, because 20980217 - 2² = 20980213 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20980217.

It is not an unprimeable number, because it can be changed into a prime (20980213) 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, 11384 + ... + 13097.

It is an arithmetic number, because the mean of its divisors is an integer number (5251389).

Almost surely, 2^20980217 is an apocalyptic number.

It is an amenable number.

20980217 is a deficient number, since it is larger than the sum of its proper divisors (25339).

20980217 is an equidigital number, since it uses as much as digits as its factorization.

20980217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25338.

The product of its (nonzero) digits is 2016, while the sum is 29.

The square root of 20980217 is about 4580.4166841020. The cubic root of 20980217 is about 275.8057558208.

The spelling of 20980217 in words is "twenty million, nine hundred eighty thousand, two hundred seventeen".