12720256957 has 2 divisors, whose sum is σ = 12720256958. Its totient is φ = 12720256956.

The previous prime is 12720256937. The next prime is 12720256963. The reversal of 12720256957 is 75965202721.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12654225081 + 66031876 = 112491^2 + 8126^2 .

It is a cyclic number.

It is not a de Polignac number, because 12720256957 - 2¹⁵ = 12720224189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12720256907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6360128478 + 6360128479.

It is an arithmetic number, because the mean of its divisors is an integer number (6360128479).

Almost surely, 2^12720256957 is an apocalyptic number.

It is an amenable number.

12720256957 is a deficient number, since it is larger than the sum of its proper divisors (1).

12720256957 is an equidigital number, since it uses as much as digits as its factorization.

12720256957 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 529200, while the sum is 46.

The spelling of 12720256957 in words is "twelve billion, seven hundred twenty million, two hundred fifty-six thousand, nine hundred fifty-seven".