16919890 has 32 divisors (see below), whose sum is σ = 33047280. Its totient is φ = 6200064.

The previous prime is 16919873. The next prime is 16919897. The reversal of 16919890 is 9891961.

It can be written as a sum of positive squares in 8 ways, for example, as 3207681 + 13712209 = 1791^2 + 3703^2 .

It is a super-2 number, since 2×16919890² = 572565355224200, which contains 22 as substring.

It is a Smith number, since the sum of its digits (43) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (16919897) 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, 19996 + ... + 20824.

Almost surely, 2^16919890 is an apocalyptic number.

16919890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

16919890 is a deficient number, since it is larger than the sum of its proper divisors (16127390).

16919890 is a wasteful number, since it uses less digits than its factorization.

16919890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1006.

The product of its (nonzero) digits is 34992, while the sum is 43.

The square root of 16919890 is about 4113.3793892613. The cubic root of 16919890 is about 256.7236300922.

The spelling of 16919890 in words is "sixteen million, nine hundred nineteen thousand, eight hundred ninety".