221289513418 has 4 divisors (see below), whose sum is σ = 331934270130. Its totient is φ = 110644756708.

The previous prime is 221289513413. The next prime is 221289513461. The reversal of 221289513418 is 814315982122.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 814315982122 = 2 ⋅407157991061.

It can be written as a sum of positive squares in only one way, i.e., 177288997249 + 44000516169 = 421057^2 + 209763^2 .

It is not an unprimeable number, because it can be changed into a prime (221289513413) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55322378353 + ... + 55322378356.

Almost surely, 2^221289513418 is an apocalyptic number.

221289513418 is a deficient number, since it is larger than the sum of its proper divisors (110644756712).

221289513418 is a wasteful number, since it uses less digits than its factorization.

221289513418 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110644756711.

The product of its digits is 276480, while the sum is 46.

The spelling of 221289513418 in words is "two hundred twenty-one billion, two hundred eighty-nine million, five hundred thirteen thousand, four hundred eighteen".