9852720021 has 6 divisors (see below), whose sum is σ = 14231706710. Its totient is φ = 6568480008.

The previous prime is 9852720019. The next prime is 9852720037. The reversal of 9852720021 is 1200272589.

9852720021 is a `hidden beast` number, since 98 + 527 + 20 + 0 + 21 = 666.

It can be written as a sum of positive squares in only one way, i.e., 9241938225 + 610781796 = 96135^2 + 24714^2 .

It is not a de Polignac number, because 9852720021 - 2¹ = 9852720019 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9852720011) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 547373326 + ... + 547373343.

Almost surely, 2^9852720021 is an apocalyptic number.

It is an amenable number.

9852720021 is a deficient number, since it is larger than the sum of its proper divisors (4378986689).

9852720021 is a wasteful number, since it uses less digits than its factorization.

9852720021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1094746675 (or 1094746672 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 9852720021 is about 99260.8685283380. The cubic root of 9852720021 is about 2143.8054992123.

The spelling of 9852720021 in words is "nine billion, eight hundred fifty-two million, seven hundred twenty thousand, twenty-one".