19445893227421 has 2 divisors, whose sum is σ = 19445893227422. Its totient is φ = 19445893227420.

The previous prime is 19445893227407. The next prime is 19445893227461. The reversal of 19445893227421 is 12472239854491.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18237289824196 + 1208603403225 = 4270514^2 + 1099365^2 .

It is a cyclic number.

It is not a de Polignac number, because 19445893227421 - 2⁹ = 19445893226909 is a prime.

It is a super-2 number, since 2×19445893227421² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 19445893227421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19445893227401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9722946613710 + 9722946613711.

It is an arithmetic number, because the mean of its divisors is an integer number (9722946613711).

Almost surely, 2^{19445893227421} is an apocalyptic number.

It is an amenable number.

19445893227421 is a deficient number, since it is larger than the sum of its proper divisors (1).

19445893227421 is an equidigital number, since it uses as much as digits as its factorization.

19445893227421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34836480, while the sum is 61.

The spelling of 19445893227421 in words is "nineteen trillion, four hundred forty-five billion, eight hundred ninety-three million, two hundred twenty-seven thousand, four hundred twenty-one".