19905439419520 has 128 divisors (see below), whose sum is σ = 47790751135680. Its totient is φ = 7928010240000.

The previous prime is 19905439419497. The next prime is 19905439419553. The reversal of 19905439419520 is 2591493450991.

It is a tau number, because it is divible by the number of its divisors (128).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 575234539 + ... + 575269141.

Almost surely, 2^{19905439419520} is an apocalyptic number.

19905439419520 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 19905439419520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23895375567840).

19905439419520 is an abundant number, since it is smaller than the sum of its proper divisors (27885311716160).

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

19905439419520 is a wasteful number, since it uses less digits than its factorization.

19905439419520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38454 (or 38442 counting only the distinct ones).

The product of its (nonzero) digits is 15746400, while the sum is 61.

The spelling of 19905439419520 in words is "nineteen trillion, nine hundred five billion, four hundred thirty-nine million, four hundred nineteen thousand, five hundred twenty".