21020022187 has 2 divisors, whose sum is σ = 21020022188. Its totient is φ = 21020022186.

The previous prime is 21020022167. The next prime is 21020022209. The reversal of 21020022187 is 78122002012.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21020022187 is a prime.

It is not a weakly prime, because it can be changed into another prime (21020022167) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510011093 + 10510011094.

It is an arithmetic number, because the mean of its divisors is an integer number (10510011094).

Almost surely, 2^21020022187 is an apocalyptic number.

21020022187 is a deficient number, since it is larger than the sum of its proper divisors (1).

21020022187 is an equidigital number, since it uses as much as digits as its factorization.

21020022187 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 896, while the sum is 25.

Adding to 21020022187 its reverse (78122002012), we get a palindrome (99142024199).

The spelling of 21020022187 in words is "twenty-one billion, twenty million, twenty-two thousand, one hundred eighty-seven".