1303123311821 has 2 divisors, whose sum is σ = 1303123311822. Its totient is φ = 1303123311820.

The previous prime is 1303123311713. The next prime is 1303123311827. The reversal of 1303123311821 is 1281133213031.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 663555238921 + 639568072900 = 814589^2 + 799730^2 .

It is a cyclic number.

It is not a de Polignac number, because 1303123311821 - 2³⁸ = 1028245404877 is a prime.

It is a super-2 number, since 2×1303123311821² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1303123311827) 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, 651561655910 + 651561655911.

It is an arithmetic number, because the mean of its divisors is an integer number (651561655911).

Almost surely, 2^{1303123311821} is an apocalyptic number.

It is an amenable number.

1303123311821 is a deficient number, since it is larger than the sum of its proper divisors (1).

1303123311821 is an equidigital number, since it uses as much as digits as its factorization.

1303123311821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592, while the sum is 29.

Adding to 1303123311821 its reverse (1281133213031), we get a palindrome (2584256524852).

The spelling of 1303123311821 in words is "one trillion, three hundred three billion, one hundred twenty-three million, three hundred eleven thousand, eight hundred twenty-one".