11871720109 has 8 divisors (see below), whose sum is σ = 12876644088. Its totient is φ = 10900861440.

The previous prime is 11871720101. The next prime is 11871720121. The reversal of 11871720109 is 90102717811.

It can be written as a sum of positive squares in 4 ways, for example, as 1424836009 + 10446884100 = 37747^2 + 102210^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 11871720109 - 2³ = 11871720101 is a prime.

It is a super-3 number, since 3×11871720109³ (a number of 31 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11871720101) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8515602 + ... + 8516995.

It is an arithmetic number, because the mean of its divisors is an integer number (1609580511).

Almost surely, 2^11871720109 is an apocalyptic number.

It is an amenable number.

11871720109 is a deficient number, since it is larger than the sum of its proper divisors (1004923979).

11871720109 is a wasteful number, since it uses less digits than its factorization.

11871720109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17032655.

The product of its (nonzero) digits is 7056, while the sum is 37.

The spelling of 11871720109 in words is "eleven billion, eight hundred seventy-one million, seven hundred twenty thousand, one hundred nine".