16551845856 has 768 divisors, whose sum is σ = 63321108480. Its totient is φ = 4138573824.

The previous prime is 16551845831. The next prime is 16551845857. The reversal of 16551845856 is 65854815561.

16551845856 is a `hidden beast` number, since 1 + 6 + 5 + 51 + 8 + 4 + 585 + 6 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16551845857) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 146476456 + ... + 146476568.

It is an arithmetic number, because the mean of its divisors is an integer number (82449360).

Almost surely, 2^16551845856 is an apocalyptic number.

16551845856 is a gapful number since it is divisible by the number (16) 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 16551845856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31660554240).

16551845856 is an abundant number, since it is smaller than the sum of its proper divisors (46769262624).

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

16551845856 is a wasteful number, since it uses less digits than its factorization.

16551845856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187 (or 161 counting only the distinct ones).

The product of its digits is 5760000, while the sum is 54.

The spelling of 16551845856 in words is "sixteen billion, five hundred fifty-one million, eight hundred forty-five thousand, eight hundred fifty-six".