1666552201 has 2 divisors, whose sum is σ = 1666552202. Its totient is φ = 1666552200.

The previous prime is 1666552189. The next prime is 1666552207. The reversal of 1666552201 is 1022556661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1513287801 + 153264400 = 38901^2 + 12380^2 .

It is a cyclic number.

It is not a de Polignac number, because 1666552201 - 2¹⁵ = 1666519433 is a prime.

It is not a weakly prime, because it can be changed into another prime (1666552207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 833276100 + 833276101.

It is an arithmetic number, because the mean of its divisors is an integer number (833276101).

Almost surely, 2^1666552201 is an apocalyptic number.

It is an amenable number.

1666552201 is a deficient number, since it is larger than the sum of its proper divisors (1).

1666552201 is an equidigital number, since it uses as much as digits as its factorization.

1666552201 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21600, while the sum is 34.

The square root of 1666552201 is about 40823.4271099328. The cubic root of 1666552201 is about 1185.6039580644.

The spelling of 1666552201 in words is "one billion, six hundred sixty-six million, five hundred fifty-two thousand, two hundred one".