19999848350161 has 9 divisors (see below), whose sum is σ = 20713413644443. Its totient is φ = 19310073187720.

The previous prime is 19999848350123. The next prime is 19999848350171. The reversal of 19999848350161 is 16105384899991.

The square root of 19999848350161 is 4472119.

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

It can be written as a sum of positive squares in only one way, i.e., 10487435341761 + 9512413008400 = 3238431^2 + 3084220^2 .

It is not a de Polignac number, because 19999848350161 - 2²⁵ = 19999814795729 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19999848350171) 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, 129614346 + ... + 129768556.

Almost surely, 2^{19999848350161} is an apocalyptic number.

19999848350161 is the 4472119-th square number.

19999848350161 is the 2236060-th centered octagonal number.

It is an amenable number.

19999848350161 is a deficient number, since it is larger than the sum of its proper divisors (713565294282).

19999848350161 is an frugal number, since it uses more digits than its factorization.

19999848350161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 308480 (or 154240 counting only the distinct ones).

The product of its (nonzero) digits is 151165440, while the sum is 73.

The spelling of 19999848350161 in words is "nineteen trillion, nine hundred ninety-nine billion, eight hundred forty-eight million, three hundred fifty thousand, one hundred sixty-one".