642738010638 has 8 divisors (see below), whose sum is σ = 1285476021288. Its totient is φ = 214246003544.

The previous prime is 642738010637. The next prime is 642738010657. The reversal of 642738010638 is 836010837246.

642738010638 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

642738010638 is an admirable number.

It is a super-2 number, since 2×642738010638² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642738010637) 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, 53561500881 + ... + 53561500892.

It is an arithmetic number, because the mean of its divisors is an integer number (160684502661).

Almost surely, 2^642738010638 is an apocalyptic number.

642738010638 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

642738010638 is a wasteful number, since it uses less digits than its factorization.

642738010638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107123001778.

The product of its (nonzero) digits is 1161216, while the sum is 48.

The spelling of 642738010638 in words is "six hundred forty-two billion, seven hundred thirty-eight million, ten thousand, six hundred thirty-eight".