19913870550016 has 99 divisors (see below), whose sum is σ = 40924130257899. Its totient is φ = 9685258518528.

The previous prime is 19913870550011. The next prime is 19913870550061. The reversal of 19913870550016 is 61005507831991.

The square root of 19913870550016 is 4462496.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 10521459942400 + 9392410607616 = 3243680^2 + 3064704^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19913870550011) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 5283593380 + ... + 5283597148.

Almost surely, 2^{19913870550016} is an apocalyptic number.

19913870550016 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

19913870550016 is the 4462496-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19913870550016

19913870550016 is an abundant number, since it is smaller than the sum of its proper divisors (21010259707883).

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

19913870550016 is an frugal number, since it uses more digits than its factorization.

19913870550016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7632 (or 3808 counting only the distinct ones).

The product of its (nonzero) digits is 2041200, while the sum is 55.

The spelling of 19913870550016 in words is "nineteen trillion, nine hundred thirteen billion, eight hundred seventy million, five hundred fifty thousand, sixteen".