19847144579 has 6 divisors (see below), whose sum is σ = 20184637380. Its totient is φ = 19509688520.

The previous prime is 19847144533. The next prime is 19847144591. The reversal of 19847144579 is 97544174891.

It is not a de Polignac number, because 19847144579 - 2¹² = 19847140483 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (59).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19847144179) 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, 1072949 + ... + 1091289.

It is an arithmetic number, because the mean of its divisors is an integer number (3364106230).

Almost surely, 2^19847144579 is an apocalyptic number.

19847144579 is a deficient number, since it is larger than the sum of its proper divisors (337492801).

19847144579 is an frugal number, since it uses more digits than its factorization.

19847144579 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36741 (or 18400 counting only the distinct ones).

The product of its digits is 10160640, while the sum is 59.

Multiplying 19847144579 by its sum of digits (59), we get a square (1170981530161 = 1082119²).

19847144579 divided by its sum of digits (59) gives a square (336392281 = 18341²).

The spelling of 19847144579 in words is "nineteen billion, eight hundred forty-seven million, one hundred forty-four thousand, five hundred seventy-nine".