643536117497 has 12 divisors (see below), whose sum is σ = 806188104036. Its totient is φ = 509171433120.

The previous prime is 643536117481. The next prime is 643536117527. The reversal of 643536117497 is 794711635346.

It can be written as a sum of positive squares in 2 ways, for example, as 240189188281 + 403346929216 = 490091^2 + 635096^2 .

It is not a de Polignac number, because 643536117497 - 2⁴ = 643536117481 is a prime.

It is a super-2 number, since 2×643536117497² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (643536117997) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 505129754 + ... + 505131027.

It is an arithmetic number, because the mean of its divisors is an integer number (67182342003).

Almost surely, 2^643536117497 is an apocalyptic number.

It is an amenable number.

643536117497 is a deficient number, since it is larger than the sum of its proper divisors (162651986539).

643536117497 is a wasteful number, since it uses less digits than its factorization.

643536117497 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1010260808 (or 1010260801 counting only the distinct ones).

The product of its digits is 11430720, while the sum is 56.

The spelling of 643536117497 in words is "six hundred forty-three billion, five hundred thirty-six million, one hundred seventeen thousand, four hundred ninety-seven".