16551661550 has 48 divisors (see below), whose sum is σ = 33721122960. Its totient is φ = 6016335360.

The previous prime is 16551661531. The next prime is 16551661589. The reversal of 16551661550 is 5516615561.

It is a junction number, because it is equal to n+sod(n) for n = 16551661498 and 16551661507.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 311084 + ... + 360383.

It is an arithmetic number, because the mean of its divisors is an integer number (702523395).

Almost surely, 2^16551661550 is an apocalyptic number.

16551661550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

16551661550 is an abundant number, since it is smaller than the sum of its proper divisors (17169461410).

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

16551661550 is a wasteful number, since it uses less digits than its factorization.

16551661550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 671525 (or 671520 counting only the distinct ones).

The product of its (nonzero) digits is 135000, while the sum is 41.

The spelling of 16551661550 in words is "sixteen billion, five hundred fifty-one million, six hundred sixty-one thousand, five hundred fifty".