642744001 has 4 divisors (see below), whose sum is σ = 643494852. Its totient is φ = 641993152.

The previous prime is 642743977. The next prime is 642744017. The reversal of 642744001 is 100447246.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 348792976 + 293951025 = 18676^2 + 17145^2 .

It is a cyclic number.

It is not a de Polignac number, because 642744001 - 2⁷ = 642743873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (642744031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 374140 + ... + 375853.

It is an arithmetic number, because the mean of its divisors is an integer number (160873713).

Almost surely, 2^642744001 is an apocalyptic number.

It is an amenable number.

642744001 is a deficient number, since it is larger than the sum of its proper divisors (750851).

642744001 is an equidigital number, since it uses as much as digits as its factorization.

642744001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 750850.

The product of its (nonzero) digits is 5376, while the sum is 28.

The square root of 642744001 is about 25352.3963561633. The cubic root of 642744001 is about 863.0037389507.

The spelling of 642744001 in words is "six hundred forty-two million, seven hundred forty-four thousand, one".