9861597757440 has 1920 divisors, whose sum is σ = 41771201472000. Its totient is φ = 2119969013760.

The previous prime is 9861597757439. The next prime is 9861597757463. The reversal of 9861597757440 is 447577951689.

9861597757440 is a `hidden beast` number, since 9 + 8 + 6 + 1 + 5 + 9 + 7 + 7 + 574 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (1920).

It is a super-2 number, since 2×9861597757440² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 124830351321 + ... + 124830351399.

It is an arithmetic number, because the mean of its divisors is an integer number (21755834100).

Almost surely, 2^{9861597757440} is an apocalyptic number.

9861597757440 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 9861597757440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20885600736000).

9861597757440 is an abundant number, since it is smaller than the sum of its proper divisors (31909603714560).

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

9861597757440 is a wasteful number, since it uses less digits than its factorization.

9861597757440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189 (or 150 counting only the distinct ones).

The product of its (nonzero) digits is 533433600, while the sum is 72.

The spelling of 9861597757440 in words is "nine trillion, eight hundred sixty-one billion, five hundred ninety-seven million, seven hundred fifty-seven thousand, four hundred forty".