643256131336 has 32 divisors (see below), whose sum is σ = 1484437227840. Its totient is φ = 254474952768.

The previous prime is 643256131319. The next prime is 643256131351. The reversal of 643256131336 is 633131652346.

It is a super-2 number, since 2×643256131336² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 643256131292 and 643256131301.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 441796066 + ... + 441797521.

It is an arithmetic number, because the mean of its divisors is an integer number (46388663370).

Almost surely, 2^643256131336 is an apocalyptic number.

It is an amenable number.

643256131336 is an abundant number, since it is smaller than the sum of its proper divisors (841181096504).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

643256131336 is a wasteful number, since it uses less digits than its factorization.

643256131336 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 883593613 (or 883593609 counting only the distinct ones).

The product of its digits is 699840, while the sum is 43.

The spelling of 643256131336 in words is "six hundred forty-three billion, two hundred fifty-six million, one hundred thirty-one thousand, three hundred thirty-six".