16042778 has 4 divisors (see below), whose sum is σ = 24064170. Its totient is φ = 8021388.

The previous prime is 16042777. The next prime is 16042787. The reversal of 16042778 is 87724061.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 87724061 = 619 ⋅141719.

It can be written as a sum of positive squares in only one way, i.e., 16024009 + 18769 = 4003^2 + 137^2 .

It is not an unprimeable number, because it can be changed into a prime (16042777) by changing a digit.

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 as a sum of consecutive naturals, namely, 4010693 + ... + 4010696.

Almost surely, 2^16042778 is an apocalyptic number.

16042778 is a deficient number, since it is larger than the sum of its proper divisors (8021392).

16042778 is an equidigital number, since it uses as much as digits as its factorization.

16042778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8021391.

The product of its (nonzero) digits is 18816, while the sum is 35.

The square root of 16042778 is about 4005.3436806347. The cubic root of 16042778 is about 252.2085805645.

The spelling of 16042778 in words is "sixteen million, forty-two thousand, seven hundred seventy-eight".