1997503856640 has 1008 divisors, whose sum is σ = 7447287595608. Its totient is φ = 513684799488.

The previous prime is 1997503856639. The next prime is 1997503856653. The reversal of 1997503856640 is 466583057991.

1997503856640 is a `hidden beast` number, since 1 + 9 + 9 + 7 + 503 + 85 + 6 + 6 + 40 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 1429880242176 + 567623614464 = 1195776^2 + 753408^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 17677025224 + ... + 17677025336.

Almost surely, 2^{1997503856640} is an apocalyptic number.

1997503856640 is a gapful number since it is divisible by the number (10) 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 1997503856640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3723643797804).

1997503856640 is an abundant number, since it is smaller than the sum of its proper divisors (5449783738968).

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

1997503856640 is an frugal number, since it uses more digits than its factorization.

1997503856640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 207 (or 160 counting only the distinct ones).

The product of its (nonzero) digits is 48988800, while the sum is 63.

The spelling of 1997503856640 in words is "one trillion, nine hundred ninety-seven billion, five hundred three million, eight hundred fifty-six thousand, six hundred forty".