1291800242533 has 2 divisors, whose sum is σ = 1291800242534. Its totient is φ = 1291800242532.

The previous prime is 1291800242501. The next prime is 1291800242539. The reversal of 1291800242533 is 3352420081921.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 983395505569 + 308404736964 = 991663^2 + 555342^2 .

It is a cyclic number.

It is not a de Polignac number, because 1291800242533 - 2⁵ = 1291800242501 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1291800242539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 645900121266 + 645900121267.

It is an arithmetic number, because the mean of its divisors is an integer number (645900121267).

Almost surely, 2^{1291800242533} is an apocalyptic number.

It is an amenable number.

1291800242533 is a deficient number, since it is larger than the sum of its proper divisors (1).

1291800242533 is an equidigital number, since it uses as much as digits as its factorization.

1291800242533 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 103680, while the sum is 40.

The spelling of 1291800242533 in words is "one trillion, two hundred ninety-one billion, eight hundred million, two hundred forty-two thousand, five hundred thirty-three".