1286856828 has 24 divisors (see below), whose sum is σ = 3336295760. Its totient is φ = 428952240.

The previous prime is 1286856821. The next prime is 1286856859. The reversal of 1286856828 is 8286586821.

It is a happy number.

1286856828 is a `hidden beast` number, since 12 + 8 + 68 + 568 + 2 + 8 = 666.

It is a super-3 number, since 3×1286856828³ (a number of 28 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1286856821) 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, 5957563 + ... + 5957778.

Almost surely, 2^1286856828 is an apocalyptic number.

1286856828 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

1286856828 is an abundant number, since it is smaller than the sum of its proper divisors (2049438932).

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

1286856828 is a wasteful number, since it uses less digits than its factorization.

1286856828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11915354 (or 11915346 counting only the distinct ones).

The product of its digits is 2949120, while the sum is 54.

The square root of 1286856828 is about 35872.7867331213. The cubic root of 1286856828 is about 1087.7023756545.

It can be divided in two parts, 12868 and 56828, that added together give a palindrome (69696).

The spelling of 1286856828 in words is "one billion, two hundred eighty-six million, eight hundred fifty-six thousand, eight hundred twenty-eight".