642638015807 has 8 divisors (see below), whose sum is σ = 650510571600. Its totient is φ = 634779946944.

The previous prime is 642638015801. The next prime is 642638015857. The reversal of 642638015807 is 708510836246.

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 642638015807 - 2¹⁶ = 642637950271 is a prime.

It is a super-2 number, since 2×642638015807² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642638015801) 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, 3532457 + ... + 3709922.

It is an arithmetic number, because the mean of its divisors is an integer number (81313821450).

Almost surely, 2^642638015807 is an apocalyptic number.

642638015807 is a deficient number, since it is larger than the sum of its proper divisors (7872555793).

642638015807 is an equidigital number, since it uses as much as digits as its factorization.

642638015807 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7243465.

The product of its (nonzero) digits is 1935360, while the sum is 50.

The spelling of 642638015807 in words is "six hundred forty-two billion, six hundred thirty-eight million, fifteen thousand, eight hundred seven".