11185720447 has 4 divisors (see below), whose sum is σ = 12202604136. Its totient is φ = 10168836760.

The previous prime is 11185720411. The next prime is 11185720459. The reversal of 11185720447 is 74402758111.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 74402758111 = 11 ⋅6763887101.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11185720447 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11185721447) 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 3 ways as a sum of consecutive naturals, for example, 508441828 + ... + 508441849.

It is an arithmetic number, because the mean of its divisors is an integer number (3050651034).

Almost surely, 2^11185720447 is an apocalyptic number.

11185720447 is a deficient number, since it is larger than the sum of its proper divisors (1016883689).

11185720447 is a wasteful number, since it uses less digits than its factorization.

11185720447 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1016883688.

The product of its (nonzero) digits is 62720, while the sum is 40.

The spelling of 11185720447 in words is "eleven billion, one hundred eighty-five million, seven hundred twenty thousand, four hundred forty-seven".