221627217529 has 9 divisors (see below), whose sum is σ = 223041394117. Its totient is φ = 220221960124.

The previous prime is 221627217509. The next prime is 221627217599. The reversal of 221627217529 is 925712726122.

It is a happy number.

The square root of 221627217529 is 470773.

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

It is not a de Polignac number, because 221627217529 - 2⁹ = 221627217017 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221627217509) 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, 78617682 + ... + 78620500.

Almost surely, 2^221627217529 is an apocalyptic number.

221627217529 is the 470773-rd square number.

221627217529 is the 235387-th centered octagonal number.

It is an amenable number.

221627217529 is a deficient number, since it is larger than the sum of its proper divisors (1414176588).

221627217529 is an frugal number, since it uses more digits than its factorization.

221627217529 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5972 (or 2986 counting only the distinct ones).

The product of its digits is 423360, while the sum is 46.

The spelling of 221627217529 in words is "two hundred twenty-one billion, six hundred twenty-seven million, two hundred seventeen thousand, five hundred twenty-nine".