16551621042 has 16 divisors (see below), whose sum is σ = 36112627872. Its totient is φ = 5015642720.

The previous prime is 16551621041. The next prime is 16551621113. The reversal of 16551621042 is 24012615561.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a junction number, because it is equal to n+sod(n) for n = 16551620994 and 16551621012.

It is not an unprimeable number, because it can be changed into a prime (16551621041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 125391003 + ... + 125391134.

It is an arithmetic number, because the mean of its divisors is an integer number (2257039242).

Almost surely, 2^16551621042 is an apocalyptic number.

16551621042 is an abundant number, since it is smaller than the sum of its proper divisors (19561006830).

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

16551621042 is a wasteful number, since it uses less digits than its factorization.

16551621042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250782153.

The product of its (nonzero) digits is 14400, while the sum is 33.

The spelling of 16551621042 in words is "sixteen billion, five hundred fifty-one million, six hundred twenty-one thousand, forty-two".