16216778 has 4 divisors (see below), whose sum is σ = 24325170. Its totient is φ = 8108388.

The previous prime is 16216763. The next prime is 16216801. The reversal of 16216778 is 87761261.

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

It can be written as a sum of positive squares in only one way, i.e., 16216729 + 49 = 4027^2 + 7^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4054193 + ... + 4054196.

Almost surely, 2^16216778 is an apocalyptic number.

16216778 is a deficient number, since it is larger than the sum of its proper divisors (8108392).

16216778 is an equidigital number, since it uses as much as digits as its factorization.

16216778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8108391.

The product of its digits is 28224, while the sum is 38.

The square root of 16216778 is about 4027.0060839289. The cubic root of 16216778 is about 253.1171220024.

The spelling of 16216778 in words is "sixteen million, two hundred sixteen thousand, seven hundred seventy-eight".