16643445 has 64 divisors (see below), whose sum is σ = 33384960. Its totient is φ = 6893568.

The previous prime is 16643401. The next prime is 16643447. The reversal of 16643445 is 54434661.

It is not a de Polignac number, because 16643445 - 2⁶ = 16643381 is a prime.

It is a super-2 number, since 2×16643445² = 554008522936050, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16643447) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 121417 + ... + 121553.

It is an arithmetic number, because the mean of its divisors is an integer number (521640).

Almost surely, 2^16643445 is an apocalyptic number.

16643445 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

16643445 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

16643445 is a wasteful number, since it uses less digits than its factorization.

16643445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 254.

The product of its digits is 34560, while the sum is 33.

The square root of 16643445 is about 4079.6378515746. The cubic root of 16643445 is about 255.3177891099.

The spelling of 16643445 in words is "sixteen million, six hundred forty-three thousand, four hundred forty-five".