1978278 has 16 divisors (see below), whose sum is σ = 4031856. Its totient is φ = 646880.

The previous prime is 1978267. The next prime is 1978289. The reversal of 1978278 is 8728791.

It is an interprime number because it is at equal distance from previous prime (1978267) and next prime (1978289).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2793 + ... + 3428.

It is an arithmetic number, because the mean of its divisors is an integer number (251991).

2^1978278 is an apocalyptic number.

1978278 is an abundant number, since it is smaller than the sum of its proper divisors (2053578).

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

1978278 is a wasteful number, since it uses less digits than its factorization.

1978278 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6279.

The product of its digits is 56448, while the sum is 42.

The square root of 1978278 is about 1406.5127087943. The cubic root of 1978278 is about 125.5343101802.

The spelling of 1978278 in words is "one million, nine hundred seventy-eight thousand, two hundred seventy-eight".