12721570643081 has 24 divisors (see below), whose sum is σ = 13451398857984. Its totient is φ = 12017609100000.

The previous prime is 12721570643077. The next prime is 12721570643137. The reversal of 12721570643081 is 18034607512721.

It is not a de Polignac number, because 12721570643081 - 2² = 12721570643077 is a prime.

It is a super-2 number, since 2×12721570643081² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12721570643281) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 15380366 + ... + 16186376.

It is an arithmetic number, because the mean of its divisors is an integer number (560474952416).

Almost surely, 2^{12721570643081} is an apocalyptic number.

It is an amenable number.

12721570643081 is a deficient number, since it is larger than the sum of its proper divisors (729828214903).

12721570643081 is an equidigital number, since it uses as much as digits as its factorization.

12721570643081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 806285 (or 806214 counting only the distinct ones).

The product of its (nonzero) digits is 564480, while the sum is 47.

The spelling of 12721570643081 in words is "twelve trillion, seven hundred twenty-one billion, five hundred seventy million, six hundred forty-three thousand, eighty-one".