72185385169 has 4 divisors (see below), whose sum is σ = 72186378660. Its totient is φ = 72184391680.

The previous prime is 72185385149. The next prime is 72185385179. The reversal of 72185385169 is 96158358127.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 71345081025 + 840304144 = 267105^2 + 28988^2 .

It is a cyclic number.

It is not a de Polignac number, because 72185385169 - 2¹¹ = 72185383121 is a prime.

It is a super-2 number, since 2×72185385169² (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 (72185385149) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 378352 + ... + 536209.

It is an arithmetic number, because the mean of its divisors is an integer number (18046594665).

Almost surely, 2^72185385169 is an apocalyptic number.

It is an amenable number.

72185385169 is a deficient number, since it is larger than the sum of its proper divisors (993491).

72185385169 is an equidigital number, since it uses as much as digits as its factorization.

72185385169 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 993490.

The product of its digits is 3628800, while the sum is 55.

The spelling of 72185385169 in words is "seventy-two billion, one hundred eighty-five million, three hundred eighty-five thousand, one hundred sixty-nine".