8126121997440 has 1152 divisors, whose sum is σ = 31107454157520. Its totient is φ = 1947677491200.

The previous prime is 8126121997439. The next prime is 8126121997463. The reversal of 8126121997440 is 447991216218.

8126121997440 is a `hidden beast` number, since 8 + 1 + 2 + 6 + 1 + 2 + 199 + 7 + 440 = 666.

It can be written as a sum of positive squares in 24 ways, for example, as 3043405855296 + 5082716142144 = 1744536^2 + 2254488^2 .

It is a tau number, because it is divible by the number of its divisors (1152).

It is a hoax number, since the sum of its digits (54) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 8317422232 + ... + 8317423208.

Almost surely, 2^{8126121997440} is an apocalyptic number.

8126121997440 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 8126121997440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15553727078760).

8126121997440 is an abundant number, since it is smaller than the sum of its proper divisors (22981332160080).

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

8126121997440 is a wasteful number, since it uses less digits than its factorization.

8126121997440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1178 (or 1134 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 54.

The spelling of 8126121997440 in words is "eight trillion, one hundred twenty-six billion, one hundred twenty-one million, nine hundred ninety-seven thousand, four hundred forty".