8921197440 has 640 divisors, whose sum is σ = 34549701120. Its totient is φ = 2185297920.

The previous prime is 8921197403. The next prime is 8921197501. The reversal of 8921197440 is 447911298.

It is a happy number.

8921197440 is a `hidden beast` number, since 8 + 92 + 119 + 7 + 440 = 666.

It is a tau number, because it is divible by the number of its divisors (640).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 46707745 + ... + 46707935.

It is an arithmetic number, because the mean of its divisors is an integer number (53983908).

Almost surely, 2^8921197440 is an apocalyptic number.

8921197440 is a gapful number since it is divisible by the number (80) 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 8921197440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17274850560).

8921197440 is an abundant number, since it is smaller than the sum of its proper divisors (25628503680).

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

8921197440 is a wasteful number, since it uses less digits than its factorization.

8921197440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 292 (or 271 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 45.

The square root of 8921197440 is about 94452.0907126994. The cubic root of 8921197440 is about 2073.9950571887.

The spelling of 8921197440 in words is "eight billion, nine hundred twenty-one million, one hundred ninety-seven thousand, four hundred forty".