642914868809 has 4 divisors (see below), whose sum is σ = 670867689216. Its totient is φ = 614962048404.

The previous prime is 642914868779. The next prime is 642914868821. The reversal of 642914868809 is 908868419246.

642914868809 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-642914868809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (642914868839) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13976410169 + ... + 13976410214.

It is an arithmetic number, because the mean of its divisors is an integer number (167716922304).

Almost surely, 2^642914868809 is an apocalyptic number.

It is an amenable number.

642914868809 is a deficient number, since it is larger than the sum of its proper divisors (27952820407).

642914868809 is a wasteful number, since it uses less digits than its factorization.

642914868809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27952820406.

The product of its (nonzero) digits is 47775744, while the sum is 65.

The spelling of 642914868809 in words is "six hundred forty-two billion, nine hundred fourteen million, eight hundred sixty-eight thousand, eight hundred nine".