1993289361921 has 135 divisors (see below), whose sum is σ = 3547296000633. Its totient is φ = 1114110391680.

The previous prime is 1993289361907. The next prime is 1993289361929. The reversal of 1993289361921 is 1291639823991.

The square root of 1993289361921 is 1411839.

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

1993289361921 is a `hidden beast` number, since 1 + 9 + 9 + 3 + 2 + 8 + 9 + 3 + 619 + 2 + 1 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 660788526321 + 1332500835600 = 812889^2 + 1154340^2 .

It is not a de Polignac number, because 1993289361921 - 2¹⁵ = 1993289329153 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1993289361929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 134 ways as a sum of consecutive naturals, for example, 1817036245 + ... + 1817037341.

Almost surely, 2^{1993289361921} is an apocalyptic number.

1993289361921 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1993289361921 is the 1411839-th square number.

1993289361921 is the 705920-th centered octagonal number.

It is an amenable number.

1993289361921 is a deficient number, since it is larger than the sum of its proper divisors (1554006638712).

1993289361921 is an equidigital number, since it uses as much as digits as its factorization.

1993289361921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2254 (or 1124 counting only the distinct ones).

The product of its digits is 11337408, while the sum is 63.

The spelling of 1993289361921 in words is "one trillion, nine hundred ninety-three billion, two hundred eighty-nine million, three hundred sixty-one thousand, nine hundred twenty-one".