643908623115 has 16 divisors (see below), whose sum is σ = 1030963862016. Its totient is φ = 343181244000.

The previous prime is 643908623107. The next prime is 643908623123. The reversal of 643908623115 is 511326809346.

It is an interprime number because it is at equal distance from previous prime (643908623107) and next prime (643908623123).

It is not a de Polignac number, because 643908623115 - 2³ = 643908623107 is a prime.

It is a super-2 number, since 2×643908623115² (a number of 24 digits) contains 22 as substring.

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, 14770531 + ... + 14814060.

It is an arithmetic number, because the mean of its divisors is an integer number (64435241376).

Almost surely, 2^643908623115 is an apocalyptic number.

643908623115 is a deficient number, since it is larger than the sum of its proper divisors (387055238901).

643908623115 is a wasteful number, since it uses less digits than its factorization.

643908623115 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29586050.

The product of its (nonzero) digits is 933120, while the sum is 48.

The spelling of 643908623115 in words is "six hundred forty-three billion, nine hundred eight million, six hundred twenty-three thousand, one hundred fifteen".