549978 has 32 divisors (see below), whose sum is σ = 1294272. Its totient is φ = 153600.

The previous prime is 549977. The next prime is 549979. The reversal of 549978 is 879945.

It is an interprime number because it is at equal distance from previous prime (549977) and next prime (549979).

It is a Curzon number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 549978.

It is not an unprimeable number, because it can be changed into a prime (549977) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 538 + ... + 1178.

It is an arithmetic number, because the mean of its divisors is an integer number (40446).

2⁵⁴⁹⁹⁷⁸ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 549978, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (647136).

549978 is an abundant number, since it is smaller than the sum of its proper divisors (744294).

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

549978 is a wasteful number, since it uses less digits than its factorization.

549978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 670.

The product of its digits is 90720, while the sum is 42.

The square root of 549978 is about 741.6050161643. The cubic root of 549978 is about 81.9310346171.

The spelling of 549978 in words is "five hundred forty-nine thousand, nine hundred seventy-eight".