19957978560000 has 1600 divisors, whose sum is σ = 74908725534720. Its totient is φ = 4686888960000.

The previous prime is 19957978559999. The next prime is 19957978560007. The reversal of 19957978560000 is 6587975991.

It is a tau number, because it is divible by the number of its divisors (1600).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19957978560007) by changing a digit.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 30563519674 + ... + 30563520326.

Almost surely, 2^{19957978560000} is an apocalyptic number.

19957978560000 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 19957978560000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37454362767360).

19957978560000 is an abundant number, since it is smaller than the sum of its proper divisors (54950746974720).

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

19957978560000 is an equidigital number, since it uses as much as digits as its factorization.

19957978560000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 817 (or 786 counting only the distinct ones).

The product of its (nonzero) digits is 42865200, while the sum is 66.

The spelling of 19957978560000 in words is "nineteen trillion, nine hundred fifty-seven billion, nine hundred seventy-eight million, five hundred sixty thousand".