221704669 has 2 divisors, whose sum is σ = 221704670. Its totient is φ = 221704668.

The previous prime is 221704657. The next prime is 221704709. The reversal of 221704669 is 966407122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 166023225 + 55681444 = 12885^2 + 7462^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221704669 is a prime.

It is a super-2 number, since 2×221704669² = 98305920512799122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221704649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110852334 + 110852335.

It is an arithmetic number, because the mean of its divisors is an integer number (110852335).

Almost surely, 2^221704669 is an apocalyptic number.

It is an amenable number.

221704669 is a deficient number, since it is larger than the sum of its proper divisors (1).

221704669 is an equidigital number, since it uses as much as digits as its factorization.

221704669 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36288, while the sum is 37.

The square root of 221704669 is about 14889.7504680233. The cubic root of 221704669 is about 605.2362704431.

The spelling of 221704669 in words is "two hundred twenty-one million, seven hundred four thousand, six hundred sixty-nine".