9897727840 has 384 divisors, whose sum is σ = 32493726720. Its totient is φ = 2748211200.

The previous prime is 9897727837. The next prime is 9897727843. The reversal of 9897727840 is 487277989.

It is an interprime number because it is at equal distance from previous prime (9897727837) and next prime (9897727843).

It is a super-2 number, since 2×9897727840² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9897727843) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4643575 + ... + 4645705.

It is an arithmetic number, because the mean of its divisors is an integer number (84619080).

Almost surely, 2^9897727840 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 9897727840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16246863360).

9897727840 is an abundant number, since it is smaller than the sum of its proper divisors (22595998880).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

9897727840 is a wasteful number, since it uses less digits than its factorization.

9897727840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2206 (or 2198 counting only the distinct ones).

The product of its (nonzero) digits is 14224896, while the sum is 61.

The square root of 9897727840 is about 99487.3250218338. The cubic root of 9897727840 is about 2147.0648854659.

It can be divided in two parts, 9897 and 727840, that added together give a palindrome (737737).

The spelling of 9897727840 in words is "nine billion, eight hundred ninety-seven million, seven hundred twenty-seven thousand, eight hundred forty".