16991988550 has 12 divisors (see below), whose sum is σ = 31605098796. Its totient is φ = 6796795400.

The previous prime is 16991988487. The next prime is 16991988557. The reversal of 16991988550 is 5588919961.

It is a super-2 number, since 2×16991988550² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16991988557) 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 5 ways as a sum of consecutive naturals, for example, 169919836 + ... + 169919935.

It is an arithmetic number, because the mean of its divisors is an integer number (2633758233).

Almost surely, 2^16991988550 is an apocalyptic number.

16991988550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

16991988550 is a deficient number, since it is larger than the sum of its proper divisors (14613110246).

16991988550 is a wasteful number, since it uses less digits than its factorization.

16991988550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 339839783 (or 339839778 counting only the distinct ones).

The product of its (nonzero) digits is 6998400, while the sum is 61.

The spelling of 16991988550 in words is "sixteen billion, nine hundred ninety-one million, nine hundred eighty-eight thousand, five hundred fifty".