115806131809 has 9 divisors (see below), whose sum is σ = 117484688659. Its totient is φ = 114151238320.

The previous prime is 115806131767. The next prime is 115806131827. The reversal of 115806131809 is 908131608511.

The square root of 115806131809 is 340303.

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

It can be written as a sum of positive squares in only one way, i.e., 100048853025 + 15757278784 = 316305^2 + 125528^2 .

It is not a de Polignac number, because 115806131809 - 2¹⁹ = 115805607521 is a prime.

It is a super-2 number, since 2×115806131809² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (115806131509) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 24159117 + ... + 24163909.

Almost surely, 2^115806131809 is an apocalyptic number.

115806131809 is the 340303-rd square number.

115806131809 is the 170152-nd centered octagonal number.

It is an amenable number.

115806131809 is a deficient number, since it is larger than the sum of its proper divisors (1678556850).

115806131809 is an frugal number, since it uses more digits than its factorization.

115806131809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9728 (or 4864 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 43.

The spelling of 115806131809 in words is "one hundred fifteen billion, eight hundred six million, one hundred thirty-one thousand, eight hundred nine".