20005047 has 6 divisors (see below), whose sum is σ = 28896192. Its totient is φ = 13336692.

The previous prime is 20005021. The next prime is 20005087. The reversal of 20005047 is 74050002.

It is a happy number.

It is not a de Polignac number, because 20005047 - 2¹² = 20000951 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20005087) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1111383 + ... + 1111400.

It is an arithmetic number, because the mean of its divisors is an integer number (4816032).

Almost surely, 2^20005047 is an apocalyptic number.

20005047 is a deficient number, since it is larger than the sum of its proper divisors (8891145).

20005047 is a wasteful number, since it uses less digits than its factorization.

20005047 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2222789 (or 2222786 counting only the distinct ones).

The product of its (nonzero) digits is 280, while the sum is 18.

The square root of 20005047 is about 4472.7001911597. The cubic root of 20005047 is about 271.4645925153.

Adding to 20005047 its reverse (74050002), we get a palindrome (94055049).

The spelling of 20005047 in words is "twenty million, five thousand, forty-seven".