16643806420 has 24 divisors (see below), whose sum is σ = 35052734304. Its totient is φ = 6638333856.

The previous prime is 16643806397. The next prime is 16643806433. The reversal of 16643806420 is 2460834661.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1192182 + ... + 1206061.

It is an arithmetic number, because the mean of its divisors is an integer number (1460530596).

Almost surely, 2^16643806420 is an apocalyptic number.

16643806420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

16643806420 is an abundant number, since it is smaller than the sum of its proper divisors (18408927884).

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

16643806420 is a wasteful number, since it uses less digits than its factorization.

16643806420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2398599 (or 2398597 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 40.

The spelling of 16643806420 in words is "sixteen billion, six hundred forty-three million, eight hundred six thousand, four hundred twenty".