642501001 has 4 divisors (see below), whose sum is σ = 647560192. Its totient is φ = 637441812.

The previous prime is 642500987. The next prime is 642501011. The reversal of 642501001 is 100105246.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 642501001 - 2¹¹ = 642498953 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 642501001.

It is not an unprimeable number, because it can be changed into a prime (642501011) 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, 2529405 + ... + 2529658.

It is an arithmetic number, because the mean of its divisors is an integer number (161890048).

Almost surely, 2^642501001 is an apocalyptic number.

It is an amenable number.

642501001 is a deficient number, since it is larger than the sum of its proper divisors (5059191).

642501001 is a wasteful number, since it uses less digits than its factorization.

642501001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5059190.

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 642501001 is about 25347.6034567373. The cubic root of 642501001 is about 862.8949676297.

Adding to 642501001 its reverse (100105246), we get a palindrome (742606247).

The spelling of 642501001 in words is "six hundred forty-two million, five hundred one thousand, one".