20028447 has 12 divisors (see below), whose sum is σ = 29057184. Its totient is φ = 13293600.

The previous prime is 20028409. The next prime is 20028457. The reversal of 20028447 is 74482002.

It is not a de Polignac number, because 20028447 - 2¹⁴ = 20012063 is a prime.

It is a super-2 number, since 2×20028447² = 802277378463618, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20028447.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20028457) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2679 + ... + 6872.

It is an arithmetic number, because the mean of its divisors is an integer number (2421432).

Almost surely, 2^20028447 is an apocalyptic number.

20028447 is a deficient number, since it is larger than the sum of its proper divisors (9028737).

20028447 is a wasteful number, since it uses less digits than its factorization.

20028447 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9790 (or 9787 counting only the distinct ones).

The product of its (nonzero) digits is 3584, while the sum is 27.

The square root of 20028447 is about 4475.3152961551. The cubic root of 20028447 is about 271.5703957544.

The spelling of 20028447 in words is "twenty million, twenty-eight thousand, four hundred forty-seven".