16749978 has 32 divisors (see below), whose sum is σ = 38724480. Its totient is φ = 4730880.

The previous prime is 16749949. The next prime is 16749979. The reversal of 16749978 is 87994761.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 16749978.

It is not an unprimeable number, because it can be changed into a prime (16749979) 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, 1498 + ... + 5978.

It is an arithmetic number, because the mean of its divisors is an integer number (1210140).

Almost surely, 2^16749978 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 16749978, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19362240).

16749978 is an abundant number, since it is smaller than the sum of its proper divisors (21974502).

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

16749978 is a wasteful number, since it uses less digits than its factorization.

16749978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4582.

The product of its digits is 762048, while the sum is 51.

The square root of 16749978 is about 4092.6736982076. The cubic root of 16749978 is about 255.8613853266.

The spelling of 16749978 in words is "sixteen million, seven hundred forty-nine thousand, nine hundred seventy-eight".