666437201 has 2 divisors, whose sum is σ = 666437202. Its totient is φ = 666437200.

The previous prime is 666437153. The next prime is 666437203. The reversal of 666437201 is 102734666.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 608904976 + 57532225 = 24676^2 + 7585^2 .

It is a cyclic number.

It is not a de Polignac number, because 666437201 - 2⁶ = 666437137 is a prime.

Together with 666437203, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (666437203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333218600 + 333218601.

It is an arithmetic number, because the mean of its divisors is an integer number (333218601).

Almost surely, 2^666437201 is an apocalyptic number.

It is an amenable number.

666437201 is a deficient number, since it is larger than the sum of its proper divisors (1).

666437201 is an equidigital number, since it uses as much as digits as its factorization.

666437201 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 35.

The square root of 666437201 is about 25815.4450087540. The cubic root of 666437201 is about 873.4802248728.

The spelling of 666437201 in words is "six hundred sixty-six million, four hundred thirty-seven thousand, two hundred one".