221178436145 has 4 divisors (see below), whose sum is σ = 265414123380. Its totient is φ = 176942748912.

The previous prime is 221178436133. The next prime is 221178436187. The reversal of 221178436145 is 541634871122.

It is a happy number.

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 107873490481 + 113304945664 = 328441^2 + 336608^2 .

It is a cyclic number.

It is not a de Polignac number, because 221178436145 - 2⁸ = 221178435889 is a prime.

It is a super-2 number, since 2×221178436145² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 221178436096 and 221178436105.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22117843610 + ... + 22117843619.

It is an arithmetic number, because the mean of its divisors is an integer number (66353530845).

Almost surely, 2^221178436145 is an apocalyptic number.

It is an amenable number.

221178436145 is a deficient number, since it is larger than the sum of its proper divisors (44235687235).

221178436145 is an equidigital number, since it uses as much as digits as its factorization.

221178436145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44235687234.

The product of its digits is 322560, while the sum is 44.

The spelling of 221178436145 in words is "two hundred twenty-one billion, one hundred seventy-eight million, four hundred thirty-six thousand, one hundred forty-five".