221937161 has 2 divisors, whose sum is σ = 221937162. Its totient is φ = 221937160.

The previous prime is 221937113. The next prime is 221937167. The reversal of 221937161 is 161739122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 217710025 + 4227136 = 14755^2 + 2056^2 .

It is a cyclic number.

It is not a de Polignac number, because 221937161 - 2¹⁰ = 221936137 is a prime.

It is a super-2 number, since 2×221937161² = 98512206865479842, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (221937167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110968580 + 110968581.

It is an arithmetic number, because the mean of its divisors is an integer number (110968581).

Almost surely, 2^221937161 is an apocalyptic number.

It is an amenable number.

221937161 is a deficient number, since it is larger than the sum of its proper divisors (1).

221937161 is an equidigital number, since it uses as much as digits as its factorization.

221937161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4536, while the sum is 32.

The square root of 221937161 is about 14897.5555377384. Note that the first 4 decimals coincide. The cubic root of 221937161 is about 605.4477581456.

The spelling of 221937161 in words is "two hundred twenty-one million, nine hundred thirty-seven thousand, one hundred sixty-one".