1556878 has 4 divisors (see below), whose sum is σ = 2335320. Its totient is φ = 778438.

The previous prime is 1556873. The next prime is 1556881. The reversal of 1556878 is 8786551.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8786551 = 97 ⋅90583.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 1556878.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1556873) by changing a digit.

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 as a sum of consecutive naturals, namely, 389218 + ... + 389221.

It is an arithmetic number, because the mean of its divisors is an integer number (583830).

2^1556878 is an apocalyptic number.

1556878 is a deficient number, since it is larger than the sum of its proper divisors (778442).

1556878 is an equidigital number, since it uses as much as digits as its factorization.

1556878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 778441.

The product of its digits is 67200, while the sum is 40.

The square root of 1556878 is about 1247.7491735120. The cubic root of 1556878 is about 115.9003801873.

The spelling of 1556878 in words is "one million, five hundred fifty-six thousand, eight hundred seventy-eight".