16555633920 has 648 divisors, whose sum is σ = 67430170080. Its totient is φ = 3739115520.

The previous prime is 16555633879. The next prime is 16555633931. The reversal of 16555633920 is 2933655561.

16555633920 is a `hidden beast` number, since 1 + 6 + 5 + 5 + 5 + 633 + 9 + 2 + 0 = 666.

16555633920 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 78462615 + ... + 78462825.

Almost surely, 2^16555633920 is an apocalyptic number.

16555633920 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 16555633920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33715085040).

16555633920 is an abundant number, since it is smaller than the sum of its proper divisors (50874536160).

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

16555633920 is a wasteful number, since it uses less digits than its factorization.

16555633920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 391 (or 367 counting only the distinct ones).

The product of its (nonzero) digits is 729000, while the sum is 45.

The spelling of 16555633920 in words is "sixteen billion, five hundred fifty-five million, six hundred thirty-three thousand, nine hundred twenty".