221216893569 has 27 divisors (see below), whose sum is σ = 371721173187. Its totient is φ = 126404009424.

The previous prime is 221216893529. The next prime is 221216893571. The reversal of 221216893569 is 965398612122.

The square root of 221216893569 is 470337.

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

221216893569 is a `hidden beast` number, since 2 + 2 + 12 + 1 + 68 + 9 + 3 + 569 = 666.

It can be written as a sum of positive squares in only one way, i.e., 213541031025 + 7675862544 = 462105^2 + 87612^2 .

It is not a de Polignac number, because 221216893569 - 2¹⁵ = 221216860801 is a prime.

It is a super-2 number, since 2×221216893569² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (221216893529) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 9865879 + ... + 9888275.

Almost surely, 2^221216893569 is an apocalyptic number.

221216893569 is the 470337-th square number.

221216893569 is the 235169-th centered octagonal number.

It is an amenable number.

221216893569 is a deficient number, since it is larger than the sum of its proper divisors (150504279618).

221216893569 is an frugal number, since it uses more digits than its factorization.

221216893569 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44814 (or 22407 counting only the distinct ones).

The product of its digits is 2799360, while the sum is 54.

The spelling of 221216893569 in words is "two hundred twenty-one billion, two hundred sixteen million, eight hundred ninety-three thousand, five hundred sixty-nine".