16721245481 has 2 divisors, whose sum is σ = 16721245482. Its totient is φ = 16721245480.

The previous prime is 16721245477. The next prime is 16721245483. The reversal of 16721245481 is 18454212761.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10716390400 + 6004855081 = 103520^2 + 77491^2 .

It is a cyclic number.

It is not a de Polignac number, because 16721245481 - 2² = 16721245477 is a prime.

It is a super-2 number, since 2×16721245481² (a number of 21 digits) contains 22 as substring.

Together with 16721245483, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (16721245483) 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, 8360622740 + 8360622741.

It is an arithmetic number, because the mean of its divisors is an integer number (8360622741).

Almost surely, 2^16721245481 is an apocalyptic number.

It is an amenable number.

16721245481 is a deficient number, since it is larger than the sum of its proper divisors (1).

16721245481 is an equidigital number, since it uses as much as digits as its factorization.

16721245481 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 107520, while the sum is 41.

The spelling of 16721245481 in words is "sixteen billion, seven hundred twenty-one million, two hundred forty-five thousand, four hundred eighty-one".