20040784 has 20 divisors (see below), whose sum is σ = 39563316. Its totient is φ = 9830912.

The previous prime is 20040781. The next prime is 20040793. The reversal of 20040784 is 48704002.

It can be written as a sum of positive squares in 2 ways, for example, as 16581184 + 3459600 = 4072^2 + 1860^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20040781) 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, 10969 + ... + 12664.

Almost surely, 2^20040784 is an apocalyptic number.

It is an amenable number.

20040784 is a deficient number, since it is larger than the sum of its proper divisors (19522532).

20040784 is a wasteful number, since it uses less digits than its factorization.

20040784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23694 (or 23688 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 25.

The square root of 20040784 is about 4476.6934226056. The cubic root of 20040784 is about 271.6261443986.

Adding to 20040784 its reverse (48704002), we get a palindrome (68744786).

The spelling of 20040784 in words is "twenty million, forty thousand, seven hundred eighty-four".