1256205517487 has 2 divisors, whose sum is σ = 1256205517488. Its totient is φ = 1256205517486.

The previous prime is 1256205517423. The next prime is 1256205517517. The reversal of 1256205517487 is 7847155026521.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1256205517487 - 2⁶ = 1256205517423 is a prime.

It is a super-3 number, since 3×1256205517487³ (a number of 37 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1256205517687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 628102758743 + 628102758744.

It is an arithmetic number, because the mean of its divisors is an integer number (628102758744).

Almost surely, 2^{1256205517487} is an apocalyptic number.

1256205517487 is a deficient number, since it is larger than the sum of its proper divisors (1).

1256205517487 is an equidigital number, since it uses as much as digits as its factorization.

1256205517487 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4704000, while the sum is 53.

The spelling of 1256205517487 in words is "one trillion, two hundred fifty-six billion, two hundred five million, five hundred seventeen thousand, four hundred eighty-seven".