20784672 has 36 divisors (see below), whose sum is σ = 59107230. Its totient is φ = 6928128.

The previous prime is 20784671. The next prime is 20784683. The reversal of 20784672 is 27648702.

It can be written as a sum of positive squares in only one way, i.e., 20466576 + 318096 = 4524^2 + 564^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (20784671) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 35797 + ... + 36372.

Almost surely, 2^20784672 is an apocalyptic number.

It is an amenable number.

20784672 is an abundant number, since it is smaller than the sum of its proper divisors (38322558).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20784672 is a wasteful number, since it uses less digits than its factorization.

20784672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72185 (or 72174 counting only the distinct ones).

The product of its (nonzero) digits is 37632, while the sum is 36.

The square root of 20784672 is about 4559.0209475281. The cubic root of 20784672 is about 274.9462021485.

The spelling of 20784672 in words is "twenty million, seven hundred eighty-four thousand, six hundred seventy-two".