19684428805 has 8 divisors (see below), whose sum is σ = 23830353432. Its totient is φ = 15608183808.

The previous prime is 19684428781. The next prime is 19684428817. The reversal of 19684428805 is 50882448691.

It can be written as a sum of positive squares in 4 ways, for example, as 50253921 + 19634174884 = 7089^2 + 140122^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 19684428805 - 2⁷ = 19684428677 is a prime.

It is a super-2 number, since 2×19684428805² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17419284 + ... + 17420413.

It is an arithmetic number, because the mean of its divisors is an integer number (2978794179).

Almost surely, 2^19684428805 is an apocalyptic number.

It is an amenable number.

19684428805 is a deficient number, since it is larger than the sum of its proper divisors (4145924627).

19684428805 is a wasteful number, since it uses less digits than its factorization.

19684428805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34839815.

The product of its (nonzero) digits is 4423680, while the sum is 55.

The spelling of 19684428805 in words is "nineteen billion, six hundred eighty-four million, four hundred twenty-eight thousand, eight hundred five".