642651216433 has 8 divisors (see below), whose sum is σ = 667343798856. Its totient is φ = 618388070400.

The previous prime is 642651216421. The next prime is 642651216443. The reversal of 642651216433 is 334612156246.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 33075969424 + 609575247009 = 181868^2 + 780753^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 642651216433 - 2⁵ = 642651216401 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 642651216433.

It is not an unprimeable number, because it can be changed into a prime (642651216443) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 107356048 + ... + 107362033.

It is an arithmetic number, because the mean of its divisors is an integer number (83417974857).

Almost surely, 2^642651216433 is an apocalyptic number.

It is an amenable number.

642651216433 is a deficient number, since it is larger than the sum of its proper divisors (24692582423).

642651216433 is a wasteful number, since it uses less digits than its factorization.

642651216433 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214718195.

The product of its digits is 622080, while the sum is 43.

The spelling of 642651216433 in words is "six hundred forty-two billion, six hundred fifty-one million, two hundred sixteen thousand, four hundred thirty-three".