643452797 has 6 divisors (see below), whose sum is σ = 696756762. Its totient is φ = 593956272.

The previous prime is 643452781. The next prime is 643452809. The reversal of 643452797 is 797254346.

It can be written as a sum of positive squares in 3 ways, for example, as 3818116 + 639634681 = 1954^2 + 25291^2 .

It is not a de Polignac number, because 643452797 - 2⁴ = 643452781 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643452707) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1903538 + ... + 1903875.

It is an arithmetic number, because the mean of its divisors is an integer number (116126127).

Almost surely, 2^643452797 is an apocalyptic number.

It is an amenable number.

643452797 is a deficient number, since it is larger than the sum of its proper divisors (53303965).

643452797 is a wasteful number, since it uses less digits than its factorization.

643452797 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3807439 (or 3807426 counting only the distinct ones).

The product of its digits is 1270080, while the sum is 47.

The square root of 643452797 is about 25366.3713802349. The cubic root of 643452797 is about 863.3208527022.

The spelling of 643452797 in words is "six hundred forty-three million, four hundred fifty-two thousand, seven hundred ninety-seven".