16550690681 has 12 divisors (see below), whose sum is σ = 19739416512. Its totient is φ = 13568172024.

The previous prime is 16550690641. The next prime is 16550690687. The reversal of 16550690681 is 18609605561.

It is a de Polignac number, because none of the positive numbers 2^k-16550690681 is a prime.

It is a super-2 number, since 2×16550690681² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16550690687) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1627310 + ... + 1637448.

It is an arithmetic number, because the mean of its divisors is an integer number (1644951376).

Almost surely, 2^16550690681 is an apocalyptic number.

It is an amenable number.

16550690681 is a deficient number, since it is larger than the sum of its proper divisors (3188725831).

16550690681 is an frugal number, since it uses more digits than its factorization.

16550690681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20308 (or 10169 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 47.

The spelling of 16550690681 in words is "sixteen billion, five hundred fifty million, six hundred ninety thousand, six hundred eighty-one".