221944261 has 16 divisors (see below), whose sum is σ = 278834688. Its totient is φ = 171615600.

The previous prime is 221944249. The next prime is 221944313. The reversal of 221944261 is 162449122.

It is a cyclic number.

It is not a de Polignac number, because 221944261 - 2⁹ = 221943749 is a prime.

It is a super-2 number, since 2×221944261² = 98518509981672242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221944201) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 915 + ... + 21088.

It is an arithmetic number, because the mean of its divisors is an integer number (17427168).

Almost surely, 2^221944261 is an apocalyptic number.

It is an amenable number.

221944261 is a deficient number, since it is larger than the sum of its proper divisors (56890427).

221944261 is a wasteful number, since it uses less digits than its factorization.

221944261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22152.

The product of its digits is 6912, while the sum is 31.

The square root of 221944261 is about 14897.7938299602. The cubic root of 221944261 is about 605.4542143773.

The spelling of 221944261 in words is "two hundred twenty-one million, nine hundred forty-four thousand, two hundred sixty-one".