642001005 has 64 divisors (see below), whose sum is σ = 1224115200. Its totient is φ = 318090240.

The previous prime is 642000991. The next prime is 642001033. The reversal of 642001005 is 500100246.

It is a happy number.

It is not a de Polignac number, because 642001005 - 2⁵ = 642000973 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 179535 + ... + 183075.

It is an arithmetic number, because the mean of its divisors is an integer number (19126800).

Almost surely, 2^642001005 is an apocalyptic number.

It is an amenable number.

642001005 is a deficient number, since it is larger than the sum of its proper divisors (582114195).

642001005 is a wasteful number, since it uses less digits than its factorization.

642001005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3651 (or 3645 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 642001005 is about 25337.7387507252. The cubic root of 642001005 is about 862.6710738163.

The spelling of 642001005 in words is "six hundred forty-two million, one thousand, five".