16554621720 has 512 divisors, whose sum is σ = 65282918400. Its totient is φ = 3260694528.

The previous prime is 16554621719. The next prime is 16554621751. The reversal of 16554621720 is 2712645561.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 15145494 + ... + 15146586.

It is an arithmetic number, because the mean of its divisors is an integer number (127505700).

Almost surely, 2^16554621720 is an apocalyptic number.

16554621720 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 16554621720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32641459200).

16554621720 is an abundant number, since it is smaller than the sum of its proper divisors (48728296680).

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

16554621720 is a wasteful number, since it uses less digits than its factorization.

16554621720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1219 (or 1215 counting only the distinct ones).

The product of its (nonzero) digits is 100800, while the sum is 39.

The spelling of 16554621720 in words is "sixteen billion, five hundred fifty-four million, six hundred twenty-one thousand, seven hundred twenty".