21225007247 has 2 divisors, whose sum is σ = 21225007248. Its totient is φ = 21225007246.

The previous prime is 21225007211. The next prime is 21225007261. The reversal of 21225007247 is 74270052212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21225007247 - 2¹⁴ = 21224990863 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21225007277) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10612503623 + 10612503624.

It is an arithmetic number, because the mean of its divisors is an integer number (10612503624).

Almost surely, 2^21225007247 is an apocalyptic number.

21225007247 is a deficient number, since it is larger than the sum of its proper divisors (1).

21225007247 is an equidigital number, since it uses as much as digits as its factorization.

21225007247 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15680, while the sum is 32.

Adding to 21225007247 its reverse (74270052212), we get a palindrome (95495059459).

The spelling of 21225007247 in words is "twenty-one billion, two hundred twenty-five million, seven thousand, two hundred forty-seven".