20215147 has 2 divisors, whose sum is σ = 20215148. Its totient is φ = 20215146.

The previous prime is 20215133. The next prime is 20215171. The reversal of 20215147 is 74151202.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20215147 - 2¹¹ = 20213099 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20215847) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10107573 + 10107574.

It is an arithmetic number, because the mean of its divisors is an integer number (10107574).

Almost surely, 2^20215147 is an apocalyptic number.

20215147 is a deficient number, since it is larger than the sum of its proper divisors (1).

20215147 is an equidigital number, since it uses as much as digits as its factorization.

20215147 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 560, while the sum is 22.

The square root of 20215147 is about 4496.1257767104. The cubic root of 20215147 is about 272.4116235589.

Adding to 20215147 its reverse (74151202), we get a palindrome (94366349).

The spelling of 20215147 in words is "twenty million, two hundred fifteen thousand, one hundred forty-seven".