9896886721 has 4 divisors (see below), whose sum is σ = 10138274244. Its totient is φ = 9655499200.

The previous prime is 9896886691. The next prime is 9896886731. The reversal of 9896886721 is 1276886989.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1276886989 = 7 ⋅182412427.

It can be written as a sum of positive squares in 2 ways, for example, as 1741893696 + 8154993025 = 41736^2 + 90305^2 .

It is a cyclic number.

It is not a de Polignac number, because 9896886721 - 2⁵ = 9896886689 is a prime.

It is a super-2 number, since 2×9896886721² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9896886731) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 120693700 + ... + 120693781.

It is an arithmetic number, because the mean of its divisors is an integer number (2534568561).

Almost surely, 2^9896886721 is an apocalyptic number.

It is an amenable number.

9896886721 is a deficient number, since it is larger than the sum of its proper divisors (241387523).

9896886721 is a wasteful number, since it uses less digits than its factorization.

9896886721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 241387522.

The product of its digits is 20901888, while the sum is 64.

The square root of 9896886721 is about 99483.0976648797. The cubic root of 9896886721 is about 2147.0040638222.

The spelling of 9896886721 in words is "nine billion, eight hundred ninety-six million, eight hundred eighty-six thousand, seven hundred twenty-one".