642642601 has 4 divisors (see below), whose sum is σ = 642703572. Its totient is φ = 642581632.

The previous prime is 642642587. The next prime is 642642629. The reversal of 642642601 is 106246246.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 280730025 + 361912576 = 16755^2 + 19024^2 .

It is a cyclic number.

It is not a de Polignac number, because 642642601 - 2¹⁵ = 642609833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (642642631) 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, 10156 + ... + 37261.

It is an arithmetic number, because the mean of its divisors is an integer number (160675893).

Almost surely, 2^642642601 is an apocalyptic number.

It is an amenable number.

642642601 is a deficient number, since it is larger than the sum of its proper divisors (60971).

642642601 is a wasteful number, since it uses less digits than its factorization.

642642601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60970.

The product of its (nonzero) digits is 13824, while the sum is 31.

The square root of 642642601 is about 25350.3964663277. The cubic root of 642642601 is about 862.9583537579.

Adding to 642642601 its reverse (106246246), we get a palindrome (748888847).

The spelling of 642642601 in words is "six hundred forty-two million, six hundred forty-two thousand, six hundred one".