19727816051 has 4 divisors (see below), whose sum is σ = 20408085600. Its totient is φ = 19047546504.

The previous prime is 19727816027. The next prime is 19727816063. The reversal of 19727816051 is 15061872791.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 19727816051 - 2²² = 19723621747 is a prime.

It is a super-2 number, since 2×19727816051² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 19727815987 and 19727816005.

It is not an unprimeable number, because it can be changed into a prime (19727816351) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 340134731 + ... + 340134788.

It is an arithmetic number, because the mean of its divisors is an integer number (5102021400).

Almost surely, 2^19727816051 is an apocalyptic number.

19727816051 is a deficient number, since it is larger than the sum of its proper divisors (680269549).

19727816051 is an equidigital number, since it uses as much as digits as its factorization.

19727816051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 680269548.

The product of its (nonzero) digits is 211680, while the sum is 47.

The spelling of 19727816051 in words is "nineteen billion, seven hundred twenty-seven million, eight hundred sixteen thousand, fifty-one".