1981247564800 has 1056 divisors, whose sum is σ = 6166923863040. Its totient is φ = 615776256000.

The previous prime is 1981247564771. The next prime is 1981247564861. The reversal of 1981247564800 is 84657421891.

It is a super-3 number, since 3×1981247564800³ (a number of 38 digits) contains 333 as substring.

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, 13120844725 + ... + 13120844875.

Almost surely, 2^{1981247564800} is an apocalyptic number.

1981247564800 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 1981247564800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3083461931520).

1981247564800 is an abundant number, since it is smaller than the sum of its proper divisors (4185676298240).

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

1981247564800 is a wasteful number, since it uses less digits than its factorization.

1981247564800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 337 (or 314 counting only the distinct ones).

The product of its (nonzero) digits is 3870720, while the sum is 55.

The spelling of 1981247564800 in words is "one trillion, nine hundred eighty-one billion, two hundred forty-seven million, five hundred sixty-four thousand, eight hundred".