642390103 has 4 divisors (see below), whose sum is σ = 642856648. Its totient is φ = 641923560.

The previous prime is 642390097. The next prime is 642390143. The reversal of 642390103 is 301093246.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-642390103 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642390143) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 231201 + ... + 233962.

It is an arithmetic number, because the mean of its divisors is an integer number (160714162).

Almost surely, 2^642390103 is an apocalyptic number.

642390103 is a deficient number, since it is larger than the sum of its proper divisors (466545).

642390103 is a wasteful number, since it uses less digits than its factorization.

642390103 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 466544.

The product of its (nonzero) digits is 3888, while the sum is 28.

The square root of 642390103 is about 25345.4158182501. The cubic root of 642390103 is about 862.8453185074.

The spelling of 642390103 in words is "six hundred forty-two million, three hundred ninety thousand, one hundred three".