185413776409 has 27 divisors (see below), whose sum is σ = 198337619199. Its totient is φ = 173306680560.

The previous prime is 185413776403. The next prime is 185413776421. The reversal of 185413776409 is 904677314581.

The square root of 185413776409 is 430597.

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., 168662169225 + 16751607184 = 410685^2 + 129428^2 .

It is not a de Polignac number, because 185413776409 - 2¹¹ = 185413774361 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 185413776409.

It is not an unprimeable number, because it can be changed into a prime (185413776403) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1071755847 + ... + 1071756019.

Almost surely, 2^185413776409 is an apocalyptic number.

185413776409 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

185413776409 is the 430597-th square number.

185413776409 is the 215299-th centered octagonal number.

It is an amenable number.

185413776409 is a deficient number, since it is larger than the sum of its proper divisors (12923842790).

185413776409 is an frugal number, since it uses more digits than its factorization.

185413776409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 646 (or 323 counting only the distinct ones).

The product of its (nonzero) digits is 5080320, while the sum is 55.

The spelling of 185413776409 in words is "one hundred eighty-five billion, four hundred thirteen million, seven hundred seventy-six thousand, four hundred nine".