1287971712 has 64 divisors (see below), whose sum is σ = 3801315600. Its totient is φ = 429322752.

The previous prime is 1287971689. The next prime is 1287971719. The reversal of 1287971712 is 2171797821.

It is a tau number, because it is divible by the number of its divisors (64).

It is a super-2 number, since 2×1287971712² = 3317742261824421888, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1287971719) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 182883 + ... + 189794.

Almost surely, 2^1287971712 is an apocalyptic number.

1287971712 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1287971712 is an abundant number, since it is smaller than the sum of its proper divisors (2513343888).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1287971712 is an equidigital number, since it uses as much as digits as its factorization.

1287971712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 372700 (or 372682 counting only the distinct ones).

The product of its digits is 98784, while the sum is 45.

The square root of 1287971712 is about 35888.3227805368. The cubic root of 1287971712 is about 1088.0163996951.

The spelling of 1287971712 in words is "one billion, two hundred eighty-seven million, nine hundred seventy-one thousand, seven hundred twelve".