1799187813421 has 2 divisors, whose sum is σ = 1799187813422. Its totient is φ = 1799187813420.

The previous prime is 1799187813347. The next prime is 1799187813443. The reversal of 1799187813421 is 1243187819971.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1798079855625 + 1107957796 = 1340925^2 + 33286^2 .

It is a cyclic number.

It is not a de Polignac number, because 1799187813421 - 2²¹ = 1799185716269 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1799187813421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1799187813821) 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 as a sum of consecutive naturals, namely, 899593906710 + 899593906711.

It is an arithmetic number, because the mean of its divisors is an integer number (899593906711).

Almost surely, 2^{1799187813421} is an apocalyptic number.

It is an amenable number.

1799187813421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1799187813421 is an equidigital number, since it uses as much as digits as its factorization.

1799187813421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6096384, while the sum is 61.

The spelling of 1799187813421 in words is "one trillion, seven hundred ninety-nine billion, one hundred eighty-seven million, eight hundred thirteen thousand, four hundred twenty-one".