1256786487 has 12 divisors (see below), whose sum is σ = 1980390984. Its totient is φ = 761688720.

The previous prime is 1256786411. The next prime is 1256786497. The reversal of 1256786487 is 7846876521.

1256786487 is a `hidden beast` number, since 1 + 25 + 67 + 86 + 487 = 666.

It is not a de Polignac number, because 1256786487 - 2⁸ = 1256786231 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1256786497) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6347308 + ... + 6347505.

It is an arithmetic number, because the mean of its divisors is an integer number (165032582).

Almost surely, 2^1256786487 is an apocalyptic number.

1256786487 is a deficient number, since it is larger than the sum of its proper divisors (723604497).

1256786487 is a wasteful number, since it uses less digits than its factorization.

1256786487 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12694830 (or 12694827 counting only the distinct ones).

The product of its digits is 4515840, while the sum is 54.

The square root of 1256786487 is about 35451.1845641299. The cubic root of 1256786487 is about 1079.1633000026.

The spelling of 1256786487 in words is "one billion, two hundred fifty-six million, seven hundred eighty-six thousand, four hundred eighty-seven".