643252471 has 2 divisors, whose sum is σ = 643252472. Its totient is φ = 643252470.

The previous prime is 643252433. The next prime is 643252541. The reversal of 643252471 is 174252346.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 643252471 - 2¹¹ = 643250423 is a prime.

It is a super-3 number, since 3×643252471³ (a number of 27 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (643259471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321626235 + 321626236.

It is an arithmetic number, because the mean of its divisors is an integer number (321626236).

Almost surely, 2^643252471 is an apocalyptic number.

643252471 is a deficient number, since it is larger than the sum of its proper divisors (1).

643252471 is an equidigital number, since it uses as much as digits as its factorization.

643252471 is an evil number, because the sum of its binary digits is even.

The product of its digits is 40320, while the sum is 34.

The square root of 643252471 is about 25362.4224197926. The cubic root of 643252471 is about 863.2312509139.

The spelling of 643252471 in words is "six hundred forty-three million, two hundred fifty-two thousand, four hundred seventy-one".