97491656640 has 448 divisors, whose sum is σ = 375427768320. Its totient is φ = 20951715840.

The previous prime is 97491656623. The next prime is 97491656653. The reversal of 97491656640 is 4665619479.

It is a tau number, because it is divible by the number of its divisors (448).

It is a super-3 number, since 3×97491656640³ (a number of 34 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 9113695 + ... + 9124385.

Almost surely, 2^97491656640 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 97491656640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (187713884160).

97491656640 is an abundant number, since it is smaller than the sum of its proper divisors (277936111680).

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

97491656640 is a wasteful number, since it uses less digits than its factorization.

97491656640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10800 (or 10790 counting only the distinct ones).

The product of its (nonzero) digits is 9797760, while the sum is 57.

The spelling of 97491656640 in words is "ninety-seven billion, four hundred ninety-one million, six hundred fifty-six thousand, six hundred forty".