11971579240009 has 3 divisors (see below), whose sum is σ = 11971582700007. Its totient is φ = 11971575780012.

The previous prime is 11971579239953. The next prime is 11971579240021. The reversal of 11971579240009 is 90004297517911.

The square root of 11971579240009 is 3459997.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 4599116148025 + 7372463091984 = 2144555^2 + 2715228^2 .

It is not a de Polignac number, because 11971579240009 - 2¹⁹ = 11971578715721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11971579240079) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 1729999 + ... + 5189995.

It is an arithmetic number, because the mean of its divisors is an integer number (3990527566669).

Almost surely, 2^{11971579240009} is an apocalyptic number.

11971579240009 is the 3459997-th square number.

11971579240009 is the 1729999-th centered octagonal number.

It is an amenable number.

11971579240009 is a deficient number, since it is larger than the sum of its proper divisors (3459998).

11971579240009 is an frugal number, since it uses more digits than its factorization.

11971579240009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6919994 (or 3459997 counting only the distinct ones).

The product of its (nonzero) digits is 1428840, while the sum is 55.

The spelling of 11971579240009 in words is "eleven trillion, nine hundred seventy-one billion, five hundred seventy-nine million, two hundred forty thousand, nine".