1664228849 has 2 divisors, whose sum is σ = 1664228850. Its totient is φ = 1664228848.

The previous prime is 1664228843. The next prime is 1664228851. The reversal of 1664228849 is 9488224661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1664068849 + 160000 = 40793^2 + 400^2 .

It is a cyclic number.

It is not a de Polignac number, because 1664228849 - 2²⁸ = 1395793393 is a prime.

It is a super-3 number, since 3×1664228849³ (a number of 29 digits) contains 333 as substring.

Together with 1664228851, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 1664228797 and 1664228806.

It is not a weakly prime, because it can be changed into another prime (1664228843) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 832114424 + 832114425.

It is an arithmetic number, because the mean of its divisors is an integer number (832114425).

Almost surely, 2^1664228849 is an apocalyptic number.

It is an amenable number.

1664228849 is a deficient number, since it is larger than the sum of its proper divisors (1).

1664228849 is an equidigital number, since it uses as much as digits as its factorization.

1664228849 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1327104, while the sum is 50.

The square root of 1664228849 is about 40794.9610736424. The cubic root of 1664228849 is about 1185.0527489323.

The spelling of 1664228849 in words is "one billion, six hundred sixty-four million, two hundred twenty-eight thousand, eight hundred forty-nine".