20181047 has 2 divisors, whose sum is σ = 20181048. Its totient is φ = 20181046.

The previous prime is 20181043. The next prime is 20181053. The reversal of 20181047 is 74018102.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20181047 - 2² = 20181043 is a prime.

It is a Chen prime.

It is equal to p_1281416 and since 20181047 and 1281416 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20181043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10090523 + 10090524.

It is an arithmetic number, because the mean of its divisors is an integer number (10090524).

Almost surely, 2^20181047 is an apocalyptic number.

20181047 is a deficient number, since it is larger than the sum of its proper divisors (1).

20181047 is an equidigital number, since it uses as much as digits as its factorization.

20181047 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 448, while the sum is 23.

The square root of 20181047 is about 4492.3320224578. The cubic root of 20181047 is about 272.2583644795.

Adding to 20181047 its reverse (74018102), we get a palindrome (94199149).

The spelling of 20181047 in words is "twenty million, one hundred eighty-one thousand, forty-seven".