1320428535551 has 2 divisors, whose sum is σ = 1320428535552. Its totient is φ = 1320428535550.

The previous prime is 1320428535533. The next prime is 1320428535577. The reversal of 1320428535551 is 1555358240231.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1320428535551 - 2³⁴ = 1303248666367 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1320428535581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660214267775 + 660214267776.

It is an arithmetic number, because the mean of its divisors is an integer number (660214267776).

Almost surely, 2^{1320428535551} is an apocalyptic number.

1320428535551 is a deficient number, since it is larger than the sum of its proper divisors (1).

1320428535551 is an equidigital number, since it uses as much as digits as its factorization.

1320428535551 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 720000, while the sum is 44.

The spelling of 1320428535551 in words is "one trillion, three hundred twenty billion, four hundred twenty-eight million, five hundred thirty-five thousand, five hundred fifty-one".