21221210147 has 2 divisors, whose sum is σ = 21221210148. Its totient is φ = 21221210146.

The previous prime is 21221210137. The next prime is 21221210167. The reversal of 21221210147 is 74101212212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21221210147 - 2¹⁶ = 21221144611 is a prime.

It is not a weakly prime, because it can be changed into another prime (21221210137) 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, 10610605073 + 10610605074.

It is an arithmetic number, because the mean of its divisors is an integer number (10610605074).

Almost surely, 2^21221210147 is an apocalyptic number.

21221210147 is a deficient number, since it is larger than the sum of its proper divisors (1).

21221210147 is an equidigital number, since it uses as much as digits as its factorization.

21221210147 is an odious number, because the sum of its binary digits is odd.

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

Adding to 21221210147 its reverse (74101212212), we get a palindrome (95322422359).

The spelling of 21221210147 in words is "twenty-one billion, two hundred twenty-one million, two hundred ten thousand, one hundred forty-seven".