21060187 has 2 divisors, whose sum is σ = 21060188. Its totient is φ = 21060186.

The previous prime is 21060181. The next prime is 21060199. The reversal of 21060187 is 78106012.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21060187 is a prime.

It is not a weakly prime, because it can be changed into another prime (21060181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10530093 + 10530094.

It is an arithmetic number, because the mean of its divisors is an integer number (10530094).

Almost surely, 2^21060187 is an apocalyptic number.

21060187 is a deficient number, since it is larger than the sum of its proper divisors (1).

21060187 is an equidigital number, since it uses as much as digits as its factorization.

21060187 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 672, while the sum is 25.

The square root of 21060187 is about 4589.1379364757. The cubic root of 21060187 is about 276.1557398357.

Adding to 21060187 its reverse (78106012), we get a palindrome (99166199).

The spelling of 21060187 in words is "twenty-one million, sixty thousand, one hundred eighty-seven".