1921803955201 has 8 divisors (see below), whose sum is σ = 2070560243304. Its totient is φ = 1773179840640.

The previous prime is 1921803955199. The next prime is 1921803955219. The reversal of 1921803955201 is 1025593081291.

It can be written as a sum of positive squares in 4 ways, for example, as 36166910976 + 1885637044225 = 190176^2 + 1373185^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1921803955201 - 2¹ = 1921803955199 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1921803905201) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33013180 + ... + 33071341.

It is an arithmetic number, because the mean of its divisors is an integer number (258820030413).

Almost surely, 2^{1921803955201} is an apocalyptic number.

It is an amenable number.

1921803955201 is a deficient number, since it is larger than the sum of its proper divisors (148756288103).

1921803955201 is a wasteful number, since it uses less digits than its factorization.

1921803955201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66086771.

The product of its (nonzero) digits is 194400, while the sum is 46.

The spelling of 1921803955201 in words is "one trillion, nine hundred twenty-one billion, eight hundred three million, nine hundred fifty-five thousand, two hundred one".