1303666421 has 2 divisors, whose sum is σ = 1303666422. Its totient is φ = 1303666420.

The previous prime is 1303666417. The next prime is 1303666439. The reversal of 1303666421 is 1246663031.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1180678321 + 122988100 = 34361^2 + 11090^2 .

It is a cyclic number.

It is not a de Polignac number, because 1303666421 - 2² = 1303666417 is a prime.

It is a super-3 number, since 3×1303666421³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1303666121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 651833210 + 651833211.

It is an arithmetic number, because the mean of its divisors is an integer number (651833211).

Almost surely, 2^1303666421 is an apocalyptic number.

It is an amenable number.

1303666421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1303666421 is an equidigital number, since it uses as much as digits as its factorization.

1303666421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15552, while the sum is 32.

The square root of 1303666421 is about 36106.3210670929. The cubic root of 1303666421 is about 1092.4179471179.

The spelling of 1303666421 in words is "one billion, three hundred three million, six hundred sixty-six thousand, four hundred twenty-one".