321681542021 has 12 divisors (see below), whose sum is σ = 381261376332. Its totient is φ = 270524636928.

The previous prime is 321681542011. The next prime is 321681542027. The reversal of 321681542021 is 120245186123.

It can be written as a sum of positive squares in 2 ways, for example, as 245113117921 + 76568424100 = 495089^2 + 276710^2 .

It is not a de Polignac number, because 321681542021 - 2¹⁰ = 321681540997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (321681542027) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 61930700 + ... + 61935893.

It is an arithmetic number, because the mean of its divisors is an integer number (31771781361).

Almost surely, 2^321681542021 is an apocalyptic number.

It is an amenable number.

321681542021 is a deficient number, since it is larger than the sum of its proper divisors (59579834311).

321681542021 is a wasteful number, since it uses less digits than its factorization.

321681542021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123866660 (or 123866653 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 35.

The spelling of 321681542021 in words is "three hundred twenty-one billion, six hundred eighty-one million, five hundred forty-two thousand, twenty-one".