21603271470721 has 2 divisors, whose sum is σ = 21603271470722. Its totient is φ = 21603271470720.

The previous prime is 21603271470667. The next prime is 21603271470757. The reversal of 21603271470721 is 12707417230612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21551692064400 + 51579406321 = 4642380^2 + 227111^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21603271470721 is a prime.

It is not a weakly prime, because it can be changed into another prime (21603271450721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10801635735360 + 10801635735361.

It is an arithmetic number, because the mean of its divisors is an integer number (10801635735361).

Almost surely, 2^{21603271470721} is an apocalyptic number.

It is an amenable number.

21603271470721 is a deficient number, since it is larger than the sum of its proper divisors (1).

21603271470721 is an equidigital number, since it uses as much as digits as its factorization.

21603271470721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 197568, while the sum is 43.

The spelling of 21603271470721 in words is "twenty-one trillion, six hundred three billion, two hundred seventy-one million, four hundred seventy thousand, seven hundred twenty-one".