16443990 has 24 divisors (see below), whose sum is σ = 42754608. Its totient is φ = 4385040.

The previous prime is 16443979. The next prime is 16443991. The reversal of 16443990 is 9934461.

16443990 is a `hidden beast` number, since 1 + 644 + 3 + 9 + 9 + 0 = 666.

It is a super-3 number, since 3×16443990³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16443991) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 91266 + ... + 91445.

It is an arithmetic number, because the mean of its divisors is an integer number (1781442).

Almost surely, 2^16443990 is an apocalyptic number.

16443990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

16443990 is an abundant number, since it is smaller than the sum of its proper divisors (26310618).

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

16443990 is a wasteful number, since it uses less digits than its factorization.

16443990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 182724 (or 182721 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 36.

The square root of 16443990 is about 4055.1189871569. The cubic root of 16443990 is about 254.2937783376.

The spelling of 16443990 in words is "sixteen million, four hundred forty-three thousand, nine hundred ninety".