1999398828001 has 3 divisors (see below), whose sum is σ = 1999400242003. Its totient is φ = 1999397414000.

The previous prime is 1999398827999. The next prime is 1999398828013. The reversal of 1999398828001 is 1008288939991.

The square root of 1999398828001 is 1414001.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 619055813601 + 1380343014400 = 786801^2 + 1174880^2 .

It is not a de Polignac number, because 1999398828001 - 2¹ = 1999398827999 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1999398828901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 707001 + ... + 2121001.

Almost surely, 2^{1999398828001} is an apocalyptic number.

1999398828001 is the 1414001-st square number.

1999398828001 is the 707001-st centered octagonal number.

It is an amenable number.

1999398828001 is a deficient number, since it is larger than the sum of its proper divisors (1414002).

1999398828001 is an frugal number, since it uses more digits than its factorization.

1999398828001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2828002 (or 1414001 counting only the distinct ones).

The product of its (nonzero) digits is 20155392, while the sum is 67.

The spelling of 1999398828001 in words is "one trillion, nine hundred ninety-nine billion, three hundred ninety-eight million, eight hundred twenty-eight thousand, one".