16639955280 has 320 divisors, whose sum is σ = 64975008000. Its totient is φ = 3880286208.

The previous prime is 16639955273. The next prime is 16639955359. The reversal of 16639955280 is 8255993661.

It is a happy number.

16639955280 is a `hidden beast` number, since 1 + 6 + 6 + 3 + 9 + 9 + 552 + 80 = 666.

It is a super-2 number, since 2×16639955280² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 517926 + ... + 549114.

It is an arithmetic number, because the mean of its divisors is an integer number (203046900).

Almost surely, 2^16639955280 is an apocalyptic number.

16639955280 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 16639955280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32487504000).

16639955280 is an abundant number, since it is smaller than the sum of its proper divisors (48335052720).

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

16639955280 is a wasteful number, since it uses less digits than its factorization.

16639955280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31243 (or 31231 counting only the distinct ones).

The product of its (nonzero) digits is 3499200, while the sum is 54.

The spelling of 16639955280 in words is "sixteen billion, six hundred thirty-nine million, nine hundred fifty-five thousand, two hundred eighty".