997991724960 has 768 divisors, whose sum is σ = 3629199168000. Its totient is φ = 256022249472.

The previous prime is 997991724923. The next prime is 997991724971. The reversal of 997991724960 is 69427199799.

997991724960 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Smith number, since the sum of its digits (72) coincides with the sum of the digits of its prime factors.

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 127 ways as a sum of consecutive naturals, for example, 3148238722 + ... + 3148239038.

It is an arithmetic number, because the mean of its divisors is an integer number (4725519750).

Almost surely, 2^997991724960 is an apocalyptic number.

997991724960 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 997991724960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1814599584000).

997991724960 is an abundant number, since it is smaller than the sum of its proper divisors (2631207443040).

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

997991724960 is a wasteful number, since it uses less digits than its factorization.

997991724960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 630 (or 616 counting only the distinct ones).

The product of its (nonzero) digits is 138883248, while the sum is 72.

The spelling of 997991724960 in words is "nine hundred ninety-seven billion, nine hundred ninety-one million, seven hundred twenty-four thousand, nine hundred sixty".