643929890311 has 8 divisors (see below), whose sum is σ = 644368744448. Its totient is φ = 643491135000.

The previous prime is 643929890299. The next prime is 643929890327. The reversal of 643929890311 is 113098929346.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a 4-Lehmer number, since φ(643929890311) divides (643929890311-1)⁴.

It is a cyclic number.

It is not a de Polignac number, because 643929890311 - 2¹¹ = 643929888263 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643929890381) by changing a digit.

It is a Zeisel number, with parameters (4, 1827).

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16736266 + ... + 16774696.

It is an arithmetic number, because the mean of its divisors is an integer number (80546093056).

Almost surely, 2^643929890311 is an apocalyptic number.

643929890311 is a deficient number, since it is larger than the sum of its proper divisors (438854137).

643929890311 is a wasteful number, since it uses less digits than its factorization.

643929890311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49413.

The product of its (nonzero) digits is 2519424, while the sum is 55.

The spelling of 643929890311 in words is "six hundred forty-three billion, nine hundred twenty-nine million, eight hundred ninety thousand, three hundred eleven".