19721272141 has 4 divisors (see below), whose sum is σ = 19744392892. Its totient is φ = 19698151392.

The previous prime is 19721272121. The next prime is 19721272147. The reversal of 19721272141 is 14127212791.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1193978916 + 18527293225 = 34554^2 + 136115^2 .

It is a cyclic number.

It is not a de Polignac number, because 19721272141 - 2¹⁹ = 19720747853 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 19721272141.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19721272147) 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, 11559096 + ... + 11560801.

It is an arithmetic number, because the mean of its divisors is an integer number (4936098223).

Almost surely, 2^19721272141 is an apocalyptic number.

It is an amenable number.

19721272141 is a deficient number, since it is larger than the sum of its proper divisors (23120751).

19721272141 is an equidigital number, since it uses as much as digits as its factorization.

19721272141 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23120750.

The product of its digits is 14112, while the sum is 37.

The spelling of 19721272141 in words is "nineteen billion, seven hundred twenty-one million, two hundred seventy-two thousand, one hundred forty-one".