1897355553481 has 2 divisors, whose sum is σ = 1897355553482. Its totient is φ = 1897355553480.

The previous prime is 1897355553439. The next prime is 1897355553521. The reversal of 1897355553481 is 1843555537981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1897186683456 + 168870025 = 1377384^2 + 12995^2 .

It is an emirp because it is prime and its reverse (1843555537981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1897355553481 - 2¹⁵ = 1897355520713 is a prime.

It is a super-2 number, since 2×1897355553481² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1897355583481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 948677776740 + 948677776741.

It is an arithmetic number, because the mean of its divisors is an integer number (948677776741).

Almost surely, 2^{1897355553481} is an apocalyptic number.

It is an amenable number.

1897355553481 is a deficient number, since it is larger than the sum of its proper divisors (1).

1897355553481 is an equidigital number, since it uses as much as digits as its factorization.

1897355553481 is an evil number, because the sum of its binary digits is even.

The product of its digits is 90720000, while the sum is 64.

The spelling of 1897355553481 in words is "one trillion, eight hundred ninety-seven billion, three hundred fifty-five million, five hundred fifty-three thousand, four hundred eighty-one".