642443107651 has 4 divisors (see below), whose sum is σ = 648447248952. Its totient is φ = 636438966352.

The previous prime is 642443107577. The next prime is 642443107673. The reversal of 642443107651 is 156701344246.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 642443107651 - 2²⁷ = 642308889923 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 642443107598 and 642443107607.

It is not an unprimeable number, because it can be changed into a prime (642443107681) 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, 3002070490 + ... + 3002070703.

It is an arithmetic number, because the mean of its divisors is an integer number (162111812238).

Almost surely, 2^642443107651 is an apocalyptic number.

642443107651 is a deficient number, since it is larger than the sum of its proper divisors (6004141301).

642443107651 is a wasteful number, since it uses less digits than its factorization.

642443107651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6004141300.

The product of its (nonzero) digits is 483840, while the sum is 43.

The spelling of 642443107651 in words is "six hundred forty-two billion, four hundred forty-three million, one hundred seven thousand, six hundred fifty-one".