1553983819321 has 2 divisors, whose sum is σ = 1553983819322. Its totient is φ = 1553983819320.

The previous prime is 1553983819307. The next prime is 1553983819343. The reversal of 1553983819321 is 1239183893551.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 833121690025 + 720862129296 = 912755^2 + 849036^2 .

It is an emirp because it is prime and its reverse (1239183893551) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1553983819321 - 2¹³ = 1553983811129 is a prime.

It is a super-2 number, since 2×1553983819321² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1553983819721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 776991909660 + 776991909661.

It is an arithmetic number, because the mean of its divisors is an integer number (776991909661).

Almost surely, 2^{1553983819321} is an apocalyptic number.

It is an amenable number.

1553983819321 is a deficient number, since it is larger than the sum of its proper divisors (1).

1553983819321 is an equidigital number, since it uses as much as digits as its factorization.

1553983819321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6998400, while the sum is 58.

The spelling of 1553983819321 in words is "one trillion, five hundred fifty-three billion, nine hundred eighty-three million, eight hundred nineteen thousand, three hundred twenty-one".