1978879 has 4 divisors (see below), whose sum is σ = 2261584. Its totient is φ = 1696176.

The previous prime is 1978877. The next prime is 1978883. The reversal of 1978879 is 9788791.

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

It is a cyclic number.

It is not a de Polignac number, because 1978879 - 2¹ = 1978877 is a prime.

It is a Duffinian number.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1978877) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 141342 + ... + 141355.

It is an arithmetic number, because the mean of its divisors is an integer number (565396).

2^1978879 is an apocalyptic number.

1978879 is a deficient number, since it is larger than the sum of its proper divisors (282705).

1978879 is an equidigital number, since it uses as much as digits as its factorization.

1978879 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 282704.

The product of its digits is 254016, while the sum is 49.

The square root of 1978879 is about 1406.7263415462. The cubic root of 1978879 is about 125.5470213161.

The spelling of 1978879 in words is "one million, nine hundred seventy-eight thousand, eight hundred seventy-nine".