1997385873840 has 480 divisors, whose sum is σ = 8275326059520. Its totient is φ = 421636368384.

The previous prime is 1997385873839. The next prime is 1997385873877. The reversal of 1997385873840 is 483785837991.

1997385873840 is a `hidden beast` number, since 1 + 9 + 9 + 7 + 3 + 8 + 587 + 38 + 4 + 0 = 666.

It is a super-3 number, since 3×1997385873840³ (a number of 38 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 95 ways as a sum of consecutive naturals, for example, 3064599 + ... + 3658761.

It is an arithmetic number, because the mean of its divisors is an integer number (17240262624).

Almost surely, 2^{1997385873840} is an apocalyptic number.

1997385873840 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 1997385873840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4137663029760).

1997385873840 is an abundant number, since it is smaller than the sum of its proper divisors (6277940185680).

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

1997385873840 is a wasteful number, since it uses less digits than its factorization.

1997385873840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 594241 (or 594232 counting only the distinct ones).

The product of its (nonzero) digits is 365783040, while the sum is 72.

The spelling of 1997385873840 in words is "one trillion, nine hundred ninety-seven billion, three hundred eighty-five million, eight hundred seventy-three thousand, eight hundred forty".