1286388 has 48 divisors (see below), whose sum is σ = 3424960. Its totient is φ = 417312.

The previous prime is 1286387. The next prime is 1286399. The reversal of 1286388 is 8836821.

1286388 is a `hidden beast` number, since 12 + 8 + 638 + 8 = 666.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1286381) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4506 + ... + 4782.

2^1286388 is an apocalyptic number.

1286388 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1286388, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1712480).

1286388 is an abundant number, since it is smaller than the sum of its proper divisors (2138572).

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

1286388 is a wasteful number, since it uses less digits than its factorization.

1286388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333 (or 325 counting only the distinct ones).

The product of its digits is 18432, while the sum is 36.

The square root of 1286388 is about 1134.1904601962. The cubic root of 1286388 is about 108.7570268943.

The spelling of 1286388 in words is "one million, two hundred eighty-six thousand, three hundred eighty-eight".