19712536441 has 4 divisors (see below), whose sum is σ = 21228885412. Its totient is φ = 18196187472.

The previous prime is 19712536409. The next prime is 19712536457. The reversal of 19712536441 is 14463521791.

It is a happy number.

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 10732131216 + 8980405225 = 103596^2 + 94765^2 .

It is a cyclic number.

It is not a de Polignac number, because 19712536441 - 2⁵ = 19712536409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19712536141) 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, 758174466 + ... + 758174491.

It is an arithmetic number, because the mean of its divisors is an integer number (5307221353).

Almost surely, 2^19712536441 is an apocalyptic number.

It is an amenable number.

19712536441 is a deficient number, since it is larger than the sum of its proper divisors (1516348971).

19712536441 is a wasteful number, since it uses less digits than its factorization.

19712536441 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1516348970.

The product of its digits is 181440, while the sum is 43.

The spelling of 19712536441 in words is "nineteen billion, seven hundred twelve million, five hundred thirty-six thousand, four hundred forty-one".