12801081781 has 4 divisors (see below), whose sum is σ = 12801639564. Its totient is φ = 12800524000.

The previous prime is 12801081773. The next prime is 12801081791. The reversal of 12801081781 is 18718010821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18718010821 = 29 ⋅645448649.

It can be written as a sum of positive squares in 2 ways, for example, as 369946756 + 12431135025 = 19234^2 + 111495^2 .

It is a cyclic number.

It is not a de Polignac number, because 12801081781 - 2³ = 12801081773 is a prime.

It is a super-2 number, since 2×12801081781² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12801081781.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12801081701) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 242920 + ... + 290881.

It is an arithmetic number, because the mean of its divisors is an integer number (3200409891).

Almost surely, 2^12801081781 is an apocalyptic number.

It is an amenable number.

12801081781 is a deficient number, since it is larger than the sum of its proper divisors (557783).

12801081781 is an equidigital number, since it uses as much as digits as its factorization.

12801081781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 557782.

The product of its (nonzero) digits is 7168, while the sum is 37.

The spelling of 12801081781 in words is "twelve billion, eight hundred one million, eighty-one thousand, seven hundred eighty-one".