642465310021 has 8 divisors (see below), whose sum is σ = 648177651864. Its totient is φ = 636753438720.

The previous prime is 642465310001. The next prime is 642465310141. The reversal of 642465310021 is 120013564246.

642465310021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 108234420100 + 534230889921 = 328990^2 + 730911^2 .

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 642465310021 - 2²⁹ = 641928439109 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 (642465310001) 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, 2987895 + ... + 3195691.

It is an arithmetic number, because the mean of its divisors is an integer number (81022206483).

Almost surely, 2^642465310021 is an apocalyptic number.

It is an amenable number.

642465310021 is a deficient number, since it is larger than the sum of its proper divisors (5712341843).

642465310021 is a wasteful number, since it uses less digits than its factorization.

642465310021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235271.

The product of its (nonzero) digits is 34560, while the sum is 34.

Adding to 642465310021 its reverse (120013564246), we get a palindrome (762478874267).

The spelling of 642465310021 in words is "six hundred forty-two billion, four hundred sixty-five million, three hundred ten thousand, twenty-one".