7997689405440 has 1568 divisors, whose sum is σ = 33356163367296. Its totient is φ = 1802101063680.

The previous prime is 7997689405427. The next prime is 7997689405471. The reversal of 7997689405440 is 445049867997.

7997689405440 is a `hidden beast` number, since 7 + 9 + 9 + 76 + 8 + 9 + 4 + 0 + 544 + 0 = 666.

It is a super-3 number, since 3×7997689405440³ (a number of 40 digits) contains 333 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 111 ways as a sum of consecutive naturals, for example, 17348566810 + ... + 17348567270.

It is an arithmetic number, because the mean of its divisors is an integer number (21273063372).

Almost surely, 2^{7997689405440} is an apocalyptic number.

7997689405440 is a gapful number since it is divisible by the number (70) 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 7997689405440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16678081683648).

7997689405440 is an abundant number, since it is smaller than the sum of its proper divisors (25358473961856).

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

7997689405440 is an frugal number, since it uses more digits than its factorization.

7997689405440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 600 (or 561 counting only the distinct ones).

The product of its (nonzero) digits is 548674560, while the sum is 72.

The spelling of 7997689405440 in words is "seven trillion, nine hundred ninety-seven billion, six hundred eighty-nine million, four hundred five thousand, four hundred forty".