2178478 has 4 divisors (see below), whose sum is σ = 3267720. Its totient is φ = 1089238.

The previous prime is 2178467. The next prime is 2178479. The reversal of 2178478 is 8748712.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2178479) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 544618 + ... + 544621.

It is an arithmetic number, because the mean of its divisors is an integer number (816930).

2^2178478 is an apocalyptic number.

2178478 is a deficient number, since it is larger than the sum of its proper divisors (1089242).

2178478 is a wasteful number, since it uses less digits than its factorization.

2178478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1089241.

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

The square root of 2178478 is about 1475.9668017947. The cubic root of 2178478 is about 129.6336430846.

The spelling of 2178478 in words is "two million, one hundred seventy-eight thousand, four hundred seventy-eight".