7725678765257 has 2 divisors, whose sum is σ = 7725678765258. Its totient is φ = 7725678765256.

The previous prime is 7725678765223. The next prime is 7725678765289. The reversal of 7725678765257 is 7525678765277.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7699897967161 + 25780798096 = 2774869^2 + 160564^2 .

It is a cyclic number.

It is not a de Polignac number, because 7725678765257 - 2²² = 7725674570953 is a prime.

It is a super-2 number, since 2×7725678765257² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (7725648765257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3862839382628 + 3862839382629.

It is an arithmetic number, because the mean of its divisors is an integer number (3862839382629).

Almost surely, 2^{7725678765257} is an apocalyptic number.

It is an amenable number.

7725678765257 is a deficient number, since it is larger than the sum of its proper divisors (1).

7725678765257 is an equidigital number, since it uses as much as digits as its factorization.

7725678765257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2420208000, while the sum is 74.

The spelling of 7725678765257 in words is "seven trillion, seven hundred twenty-five billion, six hundred seventy-eight million, seven hundred sixty-five thousand, two hundred fifty-seven".