646705201 has 2 divisors, whose sum is σ = 646705202. Its totient is φ = 646705200.

The previous prime is 646705193. The next prime is 646705243. The reversal of 646705201 is 102507646.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 646430625 + 274576 = 25425^2 + 524^2 .

It is a cyclic number.

It is not a de Polignac number, because 646705201 - 2³ = 646705193 is a prime.

It is not a weakly prime, because it can be changed into another prime (646705001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323352600 + 323352601.

It is an arithmetic number, because the mean of its divisors is an integer number (323352601).

Almost surely, 2^646705201 is an apocalyptic number.

It is an amenable number.

646705201 is a deficient number, since it is larger than the sum of its proper divisors (1).

646705201 is an equidigital number, since it uses as much as digits as its factorization.

646705201 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10080, while the sum is 31.

The square root of 646705201 is about 25430.3991514093. The cubic root of 646705201 is about 864.7729926539.

The spelling of 646705201 in words is "six hundred forty-six million, seven hundred five thousand, two hundred one".