1990493945856 has 540 divisors, whose sum is σ = 6579979148652. Its totient is φ = 576272203776.

The previous prime is 1990493945849. The next prime is 1990493945899. The reversal of 1990493945856 is 6585493940991.

1990493945856 is a `hidden beast` number, since 1 + 9 + 9 + 0 + 4 + 9 + 39 + 4 + 585 + 6 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 92160000 + 1990401785856 = 9600^2 + 1410816^2 .

It is a super-3 number, since 3×1990493945856³ (a number of 38 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 553990396 + ... + 553993988.

Almost surely, 2^{1990493945856} is an apocalyptic number.

1990493945856 is a gapful number since it is divisible by the number (16) 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 1990493945856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3289989574326).

1990493945856 is an abundant number, since it is smaller than the sum of its proper divisors (4589485202796).

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

1990493945856 is a wasteful number, since it uses less digits than its factorization.

1990493945856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3674 (or 3628 counting only the distinct ones).

The product of its (nonzero) digits is 377913600, while the sum is 72.

The spelling of 1990493945856 in words is "one trillion, nine hundred ninety billion, four hundred ninety-three million, nine hundred forty-five thousand, eight hundred fifty-six".