1331287501 has 2 divisors, whose sum is σ = 1331287502. Its totient is φ = 1331287500.

The previous prime is 1331287483. The next prime is 1331287567. The reversal of 1331287501 is 1057821331.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1262380900 + 68906601 = 35530^2 + 8301^2 .

It is a cyclic number.

It is not a de Polignac number, because 1331287501 - 2¹³ = 1331279309 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1331287571) 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, 665643750 + 665643751.

It is an arithmetic number, because the mean of its divisors is an integer number (665643751).

Almost surely, 2^1331287501 is an apocalyptic number.

It is an amenable number.

1331287501 is a deficient number, since it is larger than the sum of its proper divisors (1).

1331287501 is an equidigital number, since it uses as much as digits as its factorization.

1331287501 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5040, while the sum is 31.

The square root of 1331287501 is about 36486.8126999331. The cubic root of 1331287501 is about 1100.0791956755.

The spelling of 1331287501 in words is "one billion, three hundred thirty-one million, two hundred eighty-seven thousand, five hundred one".