98980821721 has 2 divisors, whose sum is σ = 98980821722. Its totient is φ = 98980821720.

The previous prime is 98980821713. The next prime is 98980821739. The reversal of 98980821721 is 12712808989.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 98602908121 + 377913600 = 314011^2 + 19440^2 .

It is a cyclic number.

It is not a de Polignac number, because 98980821721 - 2³ = 98980821713 is a prime.

It is not a weakly prime, because it can be changed into another prime (98980801721) 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, 49490410860 + 49490410861.

It is an arithmetic number, because the mean of its divisors is an integer number (49490410861).

Almost surely, 2^98980821721 is an apocalyptic number.

It is an amenable number.

98980821721 is a deficient number, since it is larger than the sum of its proper divisors (1).

98980821721 is an equidigital number, since it uses as much as digits as its factorization.

98980821721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1161216, while the sum is 55.

The spelling of 98980821721 in words is "ninety-eight billion, nine hundred eighty million, eight hundred twenty-one thousand, seven hundred twenty-one".