643312157835 has 16 divisors (see below), whose sum is σ = 1054404318240. Its totient is φ = 334731528960.

The previous prime is 643312157827. The next prime is 643312157867. The reversal of 643312157835 is 538751213346.

It is not a de Polignac number, because 643312157835 - 2³ = 643312157827 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 523017400 + ... + 523018629.

It is an arithmetic number, because the mean of its divisors is an integer number (65900269890).

Almost surely, 2^643312157835 is an apocalyptic number.

643312157835 is a deficient number, since it is larger than the sum of its proper divisors (411092160405).

643312157835 is a wasteful number, since it uses less digits than its factorization.

643312157835 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1046036078.

The product of its digits is 1814400, while the sum is 48.

The spelling of 643312157835 in words is "six hundred forty-three billion, three hundred twelve million, one hundred fifty-seven thousand, eight hundred thirty-five".