20684019 has 12 divisors (see below), whose sum is σ = 29297624. Its totient is φ = 12977664.

The previous prime is 20684011. The next prime is 20684021. The reversal of 20684019 is 91048602.

It is not a de Polignac number, because 20684019 - 2³ = 20684011 is a prime.

It is a super-2 number, since 2×20684019² = 855657283984722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20684011) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11062 + ... + 12795.

Almost surely, 2^20684019 is an apocalyptic number.

20684019 is a deficient number, since it is larger than the sum of its proper divisors (8613605).

20684019 is a wasteful number, since it uses less digits than its factorization.

20684019 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23894 (or 23877 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 20684019 is about 4547.9686674382. The cubic root of 20684019 is about 274.5016605684.

The spelling of 20684019 in words is "twenty million, six hundred eighty-four thousand, nineteen".