1256887864 has 8 divisors (see below), whose sum is σ = 2356664760. Its totient is φ = 628443928.

The previous prime is 1256887847. The next prime is 1256887873. The reversal of 1256887864 is 4687886521.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78555484 + ... + 78555499.

It is an arithmetic number, because the mean of its divisors is an integer number (294583095).

Almost surely, 2^1256887864 is an apocalyptic number.

It is an amenable number.

1256887864 is a deficient number, since it is larger than the sum of its proper divisors (1099776896).

1256887864 is a wasteful number, since it uses less digits than its factorization.

1256887864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157110989 (or 157110985 counting only the distinct ones).

The product of its digits is 5160960, while the sum is 55.

The square root of 1256887864 is about 35452.6143464766. The cubic root of 1256887864 is about 1079.1923156435.

The spelling of 1256887864 in words is "one billion, two hundred fifty-six million, eight hundred eighty-seven thousand, eight hundred sixty-four".