1428778 has 16 divisors (see below), whose sum is σ = 2328480. Its totient is φ = 653616.

The previous prime is 1428769. The next prime is 1428787. The reversal of 1428778 is 8778241.

It is an interprime number because it is at equal distance from previous prime (1428769) and next prime (1428787).

It is an Ulam number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4501 + ... + 4807.

It is an arithmetic number, because the mean of its divisors is an integer number (145530).

2^1428778 is an apocalyptic number.

1428778 is a deficient number, since it is larger than the sum of its proper divisors (899702).

1428778 is a wasteful number, since it uses less digits than its factorization.

1428778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 501.

The product of its digits is 25088, while the sum is 37.

The square root of 1428778 is about 1195.3150212392. The cubic root of 1428778 is about 112.6302162975.

It can be divided in two parts, 14287 and 78, that added together give a triangular number (14365 = T₁₆₉).

The spelling of 1428778 in words is "one million, four hundred twenty-eight thousand, seven hundred seventy-eight".