20684329 has 4 divisors (see below), whose sum is σ = 20823300. Its totient is φ = 20545360.

The previous prime is 20684317. The next prime is 20684341. The reversal of 20684329 is 92348602.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (20684317) and next prime (20684341).

It can be written as a sum of positive squares in 2 ways, for example, as 2408704 + 18275625 = 1552^2 + 4275^2 .

It is a cyclic number.

It is not a de Polignac number, because 20684329 - 2¹¹ = 20682281 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20684294 and 20684303.

It is not an unprimeable number, because it can be changed into a prime (20684309) 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, 69262 + ... + 69559.

It is an arithmetic number, because the mean of its divisors is an integer number (5205825).

Almost surely, 2^20684329 is an apocalyptic number.

It is an amenable number.

20684329 is a deficient number, since it is larger than the sum of its proper divisors (138971).

20684329 is a wasteful number, since it uses less digits than its factorization.

20684329 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138970.

The product of its (nonzero) digits is 20736, while the sum is 34.

The square root of 20684329 is about 4548.0027484600. The cubic root of 20684329 is about 274.5030319184.

The spelling of 20684329 in words is "twenty million, six hundred eighty-four thousand, three hundred twenty-nine".